Round Multi-Digit Numbers Practice Test

Carlos writes the number $$6,\square 48$$ where $$\square$$ represents a missing digit. If this four-digit number rounds to $$6,000$$ when rounded to the nearest thousand, what is the largest possible value for the missing digit?

The population of four towns are $$5,847$$, $$6,239$$, $$5,156$$, and $$6,891$$. A newspaper wants to report the total population rounded to the nearest ten thousand. What number should they report?