PLZ HELP ANYONE PLEASEPLZ HELP ANYONE PLEASEPLZ HELP Enter non-integer answer as a decimal.

**Notice, it is going to hit right at the point (8,175) where the arrow touches**

What is the approximate circumference of the circle shown below?

1yd 1 ft = 1 1/12 1 1/3 1 1/2 1 1/6

Atourist boat is used for sightseeing in a nearby river. the boat travels 2.4 miles downstream and in the same amount of time, it travels 1.8 miles upstream. if the boat travels at an average speed of 21 miles per hour in the still water, find the current of the river.