Modeling Periodic Phenomena with Trigonometric Functions

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Geometry › Modeling Periodic Phenomena with Trigonometric Functions

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1

In a certain city, the number of daylight hours varies sinusoidally over the year. The city has about 8 hours of daylight at its minimum (in December) and about 16 hours at its maximum (in June). The pattern repeats every 12 months. What are the amplitude and midline of a sinusoidal model for daylight hours?

Amplitude $=4$ hr, midline $=12$ hr

Amplitude $=8$ hr, midline $=12$ hr

Amplitude $=4$ hr, midline $=16$ hr

Amplitude $=12$ hr, midline $=4$ hr

Explanation

This question tests your ability to model real-world periodic phenomena using trigonometric functions by identifying key parameters—amplitude (maximum variation from center), period (time for complete cycle), and midline (center value). Periodic phenomena that repeat in regular cycles can be modeled with sine or cosine functions of the form f(t) = A·sin(B(t-C)) + D or f(t) = A·cos(B(t-C)) + D, where A is AMPLITUDE (half the total variation, calculated as (max - min)/2—represents how far values deviate from center), D is MIDLINE or vertical shift (the center line, calculated as (max + min)/2—the average value around which oscillation occurs), the PERIOD is 2π/B (time or distance for one complete cycle—how often pattern repeats), and C is phase shift (horizontal shift, where cycle starts—often 0 for simplified models). Example: tides vary from 2 ft (low) to 10 ft (high) with 12-hour period between consecutive low tides: AMPLITUDE = (10-2)/2 = 4 ft (tide varies 4 ft above and below center), MIDLINE = (10+2)/2 = 6 ft (center line is 6 ft, tide oscillates around this), PERIOD = 12 hours (pattern repeats every 12 hours), so function could be h(t) = 4cos(2π/12·t) + 6 = 4cos(πt/6) + 6 where t is hours. For daylight hours ranging from 8 to 16 hours with a 12-month repetition (though period isn't in choices, it's key context), the amplitude is (16 - 8)/2 = 4 hours, and midline is (16 + 8)/2 = 12 hours. Choice A correctly identifies these by calculating amplitude as half the range and midline as the average. Choice B doubles the amplitude, choice C shifts midline to an extreme, and choice D confuses min and max roles. Parameter extraction recipe: (1) Find MAXIMUM value from scenario (highest tide, warmest temperature, top of Ferris wheel, peak of wave). (2) Find MINIMUM value (lowest tide, coldest temperature, bottom of wheel, trough of wave). (3) Calculate AMPLITUDE = (max - min) ÷ 2 (half the total variation). Example: max 85°F, min 35°F → amplitude = (85-35)/2 = 25°F. (4) Calculate MIDLINE = (max + min) ÷ 2 (average of extremes). Example: (85+35)/2 = 60°F midline. (5) Identify PERIOD from how often pattern repeats (time between consecutive maximums or minimums, or stated cycle time). Example: temperature repeats every 12 months → period = 12 months. These three parameters (amplitude, midline, period) fully describe the periodic behavior! Quick checks: Does amplitude make sense? (Should be positive, half the total variation). Does midline split the difference? (Should be exactly between max and min). Does period match cycle description? (daily = 24 hours, yearly = 12 months or 365 days, stated rotation time). If values seem wrong, recheck calculations!

2

A Ferris wheel’s passenger height above the ground is modeled by a sinusoidal function. The minimum height is $6$ ft and the maximum height is $74$ ft. The wheel completes one rotation every $14$ minutes. What are the amplitude and period of the height function?

Amplitude $=40$ ft, period $=14$ min

Amplitude $=68$ ft, period $=14$ min

Amplitude $=34$ ft, period $=14$ min

Amplitude $=34$ ft, period $=7$ min

Explanation

This question tests your ability to model real-world periodic phenomena using trigonometric functions by identifying key parameters—amplitude (maximum variation from center), period (time for complete cycle), and midline (center value). Periodic phenomena that repeat in regular cycles can be modeled with sine or cosine functions of the form f(t) = A·sin(B(t-C)) + D or f(t) = A·cos(B(t-C)) + D, where A is AMPLITUDE (half the total variation, calculated as (max - min)/2—represents how far values deviate from center), D is MIDLINE or vertical shift (the center line, calculated as (max + min)/2—the average value around which oscillation occurs), the PERIOD is 2π/B (time or distance for one complete cycle—how often pattern repeats), and C is phase shift (horizontal shift, where cycle starts—often 0 for simplified models). For this Ferris wheel: maximum height = 74 ft, minimum height = 6 ft, so AMPLITUDE = (74 - 6)/2 = 68/2 = 34 ft (passenger moves 34 ft above and below center), and PERIOD = 14 minutes (one complete rotation). Choice A correctly identifies amplitude = 34 ft and period = 14 min by properly calculating half the range for amplitude. Choice B incorrectly uses the full range (68 ft) as amplitude instead of half, Choice C incorrectly halves the period to 7 minutes, and Choice D miscalculates the amplitude. Parameter extraction: (1) Find MAX = 74 ft and MIN = 6 ft, (2) Calculate AMPLITUDE = (74 - 6) ÷ 2 = 34 ft, (3) PERIOD = 14 minutes directly from problem—this is the time for one complete rotation!

3

In a certain city, the number of daylight hours varies sinusoidally throughout the year. The city has about 8 hours of daylight at its minimum and about 16 hours at its maximum. The cycle repeats every 12 months.

Which choice gives the correct amplitude, midline, and period for a sinusoidal daylight model?

Amplitude $=4$ hr, midline $=12$ hr, period $=6$ months

Amplitude $=4$ hr, midline $=12$ hr, period $=12$ months

Amplitude $=8$ hr, midline $=12$ hr, period $=12$ months

Amplitude $=4$ hr, midline $=16$ hr, period $=12$ months

Explanation

This question tests your ability to model real-world periodic phenomena using trigonometric functions by identifying key parameters—amplitude (maximum variation from center), period (time for complete cycle), and midline (center value). Periodic phenomena that repeat in regular cycles can be modeled with sine or cosine functions of the form f(t) = A·sin(B(t-C)) + D or f(t) = A·cos(B(t-C)) + D, where A is AMPLITUDE (half the total variation, calculated as (max - min)/2—represents how far values deviate from center), D is MIDLINE or vertical shift (the center line, calculated as (max + min)/2—the average value around which oscillation occurs), the PERIOD is 2π/B (time or distance for one complete cycle—how often pattern repeats), and C is phase shift (horizontal shift, where cycle starts—often 0 for simplified models). Example: tides vary from 2 ft (low) to 10 ft (high) with 12-hour period between consecutive low tides: AMPLITUDE = (10-2)/2 = 4 ft (tide varies 4 ft above and below center), MIDLINE = (10+2)/2 = 6 ft (center line is 6 ft, tide oscillates around this), PERIOD = 12 hours (pattern repeats every 12 hours), so function could be h(t) = 4cos(πt/6) + 6 where t is hours. Identifying these parameters from real-world context allows modeling with trigonometric functions! With daylight from 8 hr min to 16 hr max every 12 months, amplitude is (16-8)/2=4 hr, midline is (16+8)/2=12 hr, and period is 12 months. Choice A correctly identifies these by calculating half-range for amplitude, average for midline, and full cycle for period. Distractors such as B double amplitude, C shifts midline, and D halves period—watch those errors! Strategy: (1) MAX=16 hr. (2) MIN=8 hr. (3) AMPLITUDE=4 hr. (4) MIDLINE=12 hr. (5) PERIOD=12 months. Excellent progress!

4

A sinusoidal function has maximum value $18$ and minimum value $-2$, and it completes one full cycle every $5$ seconds. Which statement is correct about its amplitude, midline, and period?

Amplitude $=10$, midline $=8$, period $=5$

Amplitude $=20$, midline $=8$, period $=5$

Amplitude $=10$, midline $=8$, period $=10$

Amplitude $=10$, midline $=18$, period $=5$

Explanation

This question tests your ability to model real-world periodic phenomena using trigonometric functions by identifying key parameters—amplitude (maximum variation from center), period (time for complete cycle), and midline (center value). Periodic phenomena that repeat in regular cycles can be modeled with sine or cosine functions of the form f(t) = A·sin(B(t-C)) + D or f(t) = A·cos(B(t-C)) + D, where A is AMPLITUDE (half the total variation, calculated as (max - min)/2—represents how far values deviate from center), D is MIDLINE or vertical shift (the center line, calculated as (max + min)/2—the average value around which oscillation occurs), the PERIOD is 2π/B (time or distance for one complete cycle—how often pattern repeats), and C is phase shift (horizontal shift, where cycle starts—often 0 for simplified models). For this function: maximum = 18, minimum = -2, so AMPLITUDE = (18 - (-2))/2 = 20/2 = 10 (function varies 10 units above and below center), MIDLINE = (18 + (-2))/2 = 16/2 = 8 (center value is 8), and PERIOD = 5 seconds (given directly). Choice A correctly identifies amplitude = 10, midline = 8, and period = 5 by properly calculating parameters. Choice B incorrectly uses the full range (20) as amplitude, Choice C incorrectly uses the maximum value (18) as midline, and Choice D incorrectly doubles the period. Parameter extraction with negative minimum: (1) MAX = 18, MIN = -2, (2) AMPLITUDE = (18 - (-2)) ÷ 2 = 20 ÷ 2 = 10, (3) MIDLINE = (18 + (-2)) ÷ 2 = 16 ÷ 2 = 8, (4) PERIOD = 5 seconds as stated!

5

A sinusoidal model for the water level in a canal is based on measurements showing a maximum of $3.2\text{ m}$ and a minimum of $1.0\text{ m}$. The cycle repeats every $14$ hours. What are the amplitude and midline of the model? (Period is given.)

Amplitude $=1.1\text{ m}$, midline $=1.0\text{ m}$

Amplitude $=1.1\text{ m}$, midline $=2.1\text{ m}$

Amplitude $=1.1\text{ m}$, midline $=3.2\text{ m}$

Amplitude $=2.2\text{ m}$, midline $=2.1\text{ m}$

Explanation

This question tests your ability to model real-world periodic phenomena using trigonometric functions by identifying key parameters—amplitude (maximum variation from center), period (time for complete cycle), and midline (center value). Periodic phenomena that repeat in regular cycles can be modeled with sine or cosine functions of the form f(t) = A·sin(B(t-C)) + D or f(t) = A·cos(B(t-C)) + D, where A is AMPLITUDE (half the total variation, calculated as (max - min)/2—represents how far values deviate from center), D is MIDLINE or vertical shift (the center line, calculated as (max + min)/2—the average value around which oscillation occurs), the PERIOD is 2π/B (time or distance for one complete cycle—how often pattern repeats), and C is phase shift (horizontal shift, where cycle starts—often 0 for simplified models). For water level varying from 1.0 m (minimum) to 3.2 m (maximum): AMPLITUDE = (3.2-1.0)/2 = 2.2/2 = 1.1 m (water level varies 1.1 m above and below center), MIDLINE = (3.2+1.0)/2 = 4.2/2 = 2.1 m (average water level). Choice B correctly identifies these parameters: amplitude = 1.1 m and midline = 2.1 m. Choice A incorrectly uses the full range (2.2 m) as amplitude instead of half the range; remember amplitude is the maximum deviation from the center line, not the total variation. Parameter extraction recipe: (1) Find MAXIMUM value = 3.2 m. (2) Find MINIMUM value = 1.0 m. (3) Calculate AMPLITUDE = (max - min) ÷ 2 = (3.2-1.0)/2 = 1.1 m. (4) Calculate MIDLINE = (max + min) ÷ 2 = (3.2+1.0)/2 = 2.1 m. Quick checks: Water level goes 1.1 m above midline (2.1+1.1=3.2 ✓) and 1.1 m below midline (2.1-1.1=1.0 ✓). The midline of 2.1 m is exactly halfway between the extremes!

6

The tide height at a pier varies sinusoidally between 2 ft (low tide) and 10 ft (high tide). The time between consecutive high tides is 12 hours. What are the amplitude, midline, and period of a sinusoidal model of the tide height?

Amplitude $=4$ ft, midline $=10$ ft, period $=12$ hr

Amplitude $=8$ ft, midline $=6$ ft, period $=12$ hr

Amplitude $=4$ ft, midline $=6$ ft, period $=12$ hr

Amplitude $=4$ ft, midline $=6$ ft, period $=6$ hr

Explanation

This question tests your ability to model real-world periodic phenomena using trigonometric functions by identifying key parameters—amplitude (maximum variation from center), period (time for complete cycle), and midline (center value). Periodic phenomena that repeat in regular cycles can be modeled with sine or cosine functions of the form f(t) = A·sin(B(t-C)) + D or f(t) = A·cos(B(t-C)) + D, where A is AMPLITUDE (half the total variation, calculated as (max - min)/2—represents how far values deviate from center), D is MIDLINE or vertical shift (the center line, calculated as (max + min)/2—the average value around which oscillation occurs), the PERIOD is 2π/B (time or distance for one complete cycle—how often pattern repeats), and C is phase shift (horizontal shift, where cycle starts—often 0 for simplified models). Example: tides vary from 2 ft (low) to 10 ft (high) with 12-hour period between consecutive low tides: AMPLITUDE = (10-2)/2 = 4 ft (tide varies 4 ft above and below center), MIDLINE = (10+2)/2 = 6 ft (center line is 6 ft, tide oscillates around this), PERIOD = 12 hours (pattern repeats every 12 hours), so function could be h(t) = 4cos(2π/12·t) + 6 = 4cos(πt/6) + 6 where t is hours. In this tide scenario, with heights ranging from 2 ft to 10 ft and 12 hours between consecutive high tides (which is the period for the tidal cycle), the amplitude is (10 - 2)/2 = 4 ft, midline is (10 + 2)/2 = 6 ft, and period is 12 hours. Choice B correctly identifies these parameters by properly calculating amplitude as half the range, midline as the average, and period from the time between highs. Choice A mistakenly doubles the amplitude to the full range, choice C uses the maximum as midline, and choice D halves the period. Parameter extraction recipe: (1) Find MAXIMUM value from scenario (highest tide, warmest temperature, top of Ferris wheel, peak of wave). (2) Find MINIMUM value (lowest tide, coldest temperature, bottom of wheel, trough of wave). (3) Calculate AMPLITUDE = (max - min) ÷ 2 (half the total variation). Example: max 85°F, min 35°F → amplitude = (85-35)/2 = 25°F. (4) Calculate MIDLINE = (max + min) ÷ 2 (average of extremes). Example: (85+35)/2 = 60°F midline. (5) Identify PERIOD from how often pattern repeats (time between consecutive maximums or minimums, or stated cycle time). Example: temperature repeats every 12 months → period = 12 months. These three parameters (amplitude, midline, period) fully describe the periodic behavior! Quick checks: Does amplitude make sense? (Should be positive, half the total variation). Does midline split the difference? (Should be exactly between max and min). Does period match cycle description? (daily = 24 hours, yearly = 12 months or 365 days, stated rotation time). If values seem wrong, recheck calculations!

7

In a harbor, the tide height ranges from a low of $1.5\text{ ft}$ to a high of $9.5\text{ ft}$. The time from one high tide to the next high tide is $12$ hours. What are the amplitude, midline, and period of a sinusoidal model for tide height?

Amplitude $=4\text{ ft}$, midline $=5.5\text{ ft}$, period $=6\text{ hr}$

Amplitude $=4\text{ ft}$, midline $=5.5\text{ ft}$, period $=12\text{ hr}$

Amplitude $=4\text{ ft}$, midline $=9.5\text{ ft}$, period $=12\text{ hr}$

Amplitude $=8\text{ ft}$, midline $=5.5\text{ ft}$, period $=12\text{ hr}$

Explanation

This question tests your ability to model real-world periodic phenomena using trigonometric functions by identifying key parameters—amplitude (maximum variation from center), period (time for complete cycle), and midline (center value). Periodic phenomena that repeat in regular cycles can be modeled with sine or cosine functions of the form f(t) = A·sin(B(t-C)) + D or f(t) = A·cos(B(t-C)) + D, where A is AMPLITUDE (half the total variation, calculated as (max - min)/2—represents how far values deviate from center), D is MIDLINE or vertical shift (the center line, calculated as (max + min)/2—the average value around which oscillation occurs), the PERIOD is 2π/B (time or distance for one complete cycle—how often pattern repeats), and C is phase shift (horizontal shift, where cycle starts—often 0 for simplified models). For these tides ranging from 1.5 ft (low) to 9.5 ft (high) with 12-hour cycle: AMPLITUDE = (9.5-1.5)/2 = 8/2 = 4 ft (tide varies 4 ft above and below center), MIDLINE = (9.5+1.5)/2 = 11/2 = 5.5 ft (center line is 5.5 ft, tide oscillates around this), and PERIOD = 12 hours (time from high tide to next high tide). Choice B correctly identifies all parameters: amplitude = 4 ft, midline = 5.5 ft, and period = 12 hours. Choice A incorrectly uses the full range (8 ft) as amplitude instead of half the range; remember amplitude measures deviation from center, not total variation. Parameter extraction recipe: (1) Find MAXIMUM value = 9.5 ft (high tide). (2) Find MINIMUM value = 1.5 ft (low tide). (3) Calculate AMPLITUDE = (max - min) ÷ 2 = (9.5-1.5)/2 = 4 ft. (4) Calculate MIDLINE = (max + min) ÷ 2 = (9.5+1.5)/2 = 5.5 ft. (5) Identify PERIOD = 12 hours (given as time between consecutive high tides). Quick checks: Does amplitude make sense? (4 ft is positive and half of 8 ft range ✓). Does midline split the difference? (5.5 is exactly between 1.5 and 9.5 ✓). Does period match description? (12 hours for tidal cycle ✓)!

8

A buoy moves up and down with the waves. Its vertical displacement from the calm-water level ranges from $-2$ m (lowest) to $+2$ m (highest). One complete up-and-down cycle takes 8 seconds. What are the amplitude, midline, and period for a sinusoidal model of the buoy’s displacement?

Amplitude $=2$ m, midline $=-2$ m, period $=8$ s

Amplitude $=4$ m, midline $=0$ m, period $=8$ s

Amplitude $=2$ m, midline $=0$ m, period $=4$ s

Amplitude $=2$ m, midline $=0$ m, period $=8$ s

Explanation

This question tests your ability to model real-world periodic phenomena using trigonometric functions by identifying key parameters—amplitude (maximum variation from center), period (time for complete cycle), and midline (center value). Periodic phenomena that repeat in regular cycles can be modeled with sine or cosine functions of the form f(t) = A·sin(B(t-C)) + D or f(t) = A·cos(B(t-C)) + D, where A is AMPLITUDE (half the total variation, calculated as (max - min)/2—represents how far values deviate from center), D is MIDLINE or vertical shift (the center line, calculated as (max + min)/2—the average value around which oscillation occurs), the PERIOD is 2π/B (time or distance for one complete cycle—how often pattern repeats), and C is phase shift (horizontal shift, where cycle starts—often 0 for simplified models). Example: tides vary from 2 ft (low) to 10 ft (high) with 12-hour period between consecutive low tides: AMPLITUDE = (10-2)/2 = 4 ft (tide varies 4 ft above and below center), MIDLINE = (10+2)/2 = 6 ft (center line is 6 ft, tide oscillates around this), PERIOD = 12 hours (pattern repeats every 12 hours), so function could be h(t) = 4cos(2π/12·t) + 6 = 4cos(πt/6) + 6 where t is hours. For the buoy displacing from -2 m to +2 m with an 8-second cycle, amplitude is (2 - (-2))/2 = 2 m, midline is (2 + (-2))/2 = 0 m (calm-water level), and period is 8 seconds. Choice B correctly identifies these by calculating amplitude as half the range, midline as the average, and period from the cycle time. Choice A doubles amplitude, choice C shifts midline negatively, and choice D halves the period. Parameter extraction recipe: (1) Find MAXIMUM value from scenario (highest tide, warmest temperature, top of Ferris wheel, peak of wave). (2) Find MINIMUM value (lowest tide, coldest temperature, bottom of wheel, trough of wave). (3) Calculate AMPLITUDE = (max - min) ÷ 2 (half the total variation). Example: max 85°F, min 35°F → amplitude = (85-35)/2 = 25°F. (4) Calculate MIDLINE = (max + min) ÷ 2 (average of extremes). Example: (85+35)/2 = 60°F midline. (5) Identify PERIOD from how often pattern repeats (time between consecutive maximums or minimums, or stated cycle time). Example: temperature repeats every 12 months → period = 12 months. These three parameters (amplitude, midline, period) fully describe the periodic behavior! Quick checks: Does amplitude make sense? (Should be positive, half the total variation). Does midline split the difference? (Should be exactly between max and min). Does period match cycle description? (daily = 24 hours, yearly = 12 months or 365 days, stated rotation time). If values seem wrong, recheck calculations!

9

The water level in a harbor is modeled by a sinusoidal function. The midline water level is 7 ft, and the amplitude is 3 ft. The time between consecutive high tides is 12 hours.

Which choice gives the correct maximum and minimum water levels and the period?

Maximum $=10$ ft, minimum $=4$ ft, period $=6$ hr

Maximum $=7$ ft, minimum $=4$ ft, period $=12$ hr

Maximum $=10$ ft, minimum $=4$ ft, period $=12$ hr

Maximum $=10$ ft, minimum $=7$ ft, period $=12$ hr

Explanation

This question tests your ability to model real-world periodic phenomena using trigonometric functions by identifying key parameters—amplitude (maximum variation from center), period (time for complete cycle), and midline (center value). Periodic phenomena that repeat in regular cycles can be modeled with sine or cosine functions of the form f(t) = A·sin(B(t-C)) + D or f(t) = A·cos(B(t-C)) + D, where A is AMPLITUDE (half the total variation, calculated as (max - min)/2—represents how far values deviate from center), D is MIDLINE or vertical shift (the center line, calculated as (max + min)/2—the average value around which oscillation occurs), the PERIOD is 2π/B (time or distance for one complete cycle—how often pattern repeats), and C is phase shift (horizontal shift, where cycle starts—often 0 for simplified models). Example: tides vary from 2 ft (low) to 10 ft (high) with 12-hour period between consecutive low tides: AMPLITUDE = (10-2)/2 = 4 ft (tide varies 4 ft above and below center), MIDLINE = (10+2)/2 = 6 ft (center line is 6 ft, tide oscillates around this), PERIOD = 12 hours (pattern repeats every 12 hours), so function could be h(t) = 4cos(πt/6) + 6 where t is hours. Identifying these parameters from real-world context allows modeling with trigonometric functions! Given midline 7 ft and amplitude 3 ft, max is 7+3=10 ft, min 7-3=4 ft, period 12 hr between highs. Choice A correctly derives max/min from parameters and uses full period. Distractors alter min or halve period—reverse calculate properly. Recipe: Max = midline + amp, min = midline - amp, period as given cycle. Awesome!

10

A Ferris wheel has a diameter of 50 m, and the center of the wheel is 30 m above the ground. The wheel makes one full rotation every 8 minutes. A rider starts at the top of the wheel at time $t=0$.

Which set of parameters correctly describes a cosine model for the rider’s height above the ground (amplitude, period, midline)?

Amplitude $=30$ m, period $=8$ min, midline $=25$ m

Amplitude $=50$ m, period $=8$ min, midline $=30$ m

Amplitude $=25$ m, period $=8$ min, midline $=30$ m

Amplitude $=25$ m, period $=4$ min, midline $=30$ m

Explanation

This question tests your ability to model real-world periodic phenomena using trigonometric functions by identifying key parameters—amplitude (maximum variation from center), period (time for complete cycle), and midline (center value). Periodic phenomena that repeat in regular cycles can be modeled with sine or cosine functions of the form f(t) = A·sin(B(t-C)) + D or f(t) = A·cos(B(t-C)) + D, where A is AMPLITUDE (half the total variation, calculated as (max - min)/2—represents how far values deviate from center), D is MIDLINE or vertical shift (the center line, calculated as (max + min)/2—the average value around which oscillation occurs), the PERIOD is 2π/B (time or distance for one complete cycle—how often pattern repeats), and C is phase shift (horizontal shift, where cycle starts—often 0 for simplified models). Example: tides vary from 2 ft (low) to 10 ft (high) with 12-hour period between consecutive low tides: AMPLITUDE = (10-2)/2 = 4 ft (tide varies 4 ft above and below center), MIDLINE = (10+2)/2 = 6 ft (center line is 6 ft, tide oscillates around this), PERIOD = 12 hours (pattern repeats every 12 hours), so function could be h(t) = 4cos(πt/6) + 6 where t is hours. Identifying these parameters from real-world context allows modeling with trigonometric functions! For this Ferris wheel with diameter 50 m (so radius 25 m, height from 30-25=5 m to 30+25=55 m), the amplitude is (55-5)/2=25 m, midline is (55+5)/2=30 m (center height), and period is 8 minutes for one rotation. Choice B correctly identifies these parameters by properly calculating amplitude as half the range, midline as average, and period from cycle repetition time. A common distractor like Choice A uses the full diameter as amplitude instead of half, while Choice C halves the period incorrectly, and Choice D swaps values erroneously. Remember the parameter extraction recipe: (1) Find MAXIMUM value from scenario (top of Ferris wheel at 55 m). (2) Find MINIMUM value (bottom at 5 m). (3) Calculate AMPLITUDE = (max - min) ÷ 2 = 25 m. (4) Calculate MIDLINE = (max + min) ÷ 2 = 30 m. (5) Identify PERIOD from how often pattern repeats (8 minutes per rotation). These three parameters fully describe the periodic behavior! Quick checks: amplitude positive and half variation? Midline between max and min? Period matches cycle? Great job verifying!

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