How do you round 6.512 459 to the nearest ten-thousandth?

The parabola opens: y=√x-4 (principal square root) up down right left

Acomputer store bought a program at a cost of $10 and sold it for $13. find the percent markup

Aremote-controlled boat can travel at 4 feet per second in calm water. the boat traveled 48 feet with the current, and then it traveled 16 feet against the current in the same amount of time. how fast is the current?