The area of a circle that's 64 pi square inches long. what's the radius ?

Atrain leaves little? rock, arkansas, and travels north at 90 kilometers per hour. another train leaves at the same time and travels south at 80 kilometers per hour. how long will it take before they are 680 kilometers? apart?

Arectangle plot measure 20ft. by 30ft. a 3-ft.-wide sidewalk surrounds it.find the area of the sidewalk.

Aregular hexagonal pyramid has a base area of 45 in2 and a lateral area of 135in 2. what is the surface are are of the regular hexagonal pyramid