Johnny painted a tabletop that is shaped like a circle. The circumference of the tabletop is 8cm feet. What is the area of the tabletop in square feet? answer ASAP

Technicians have installed a center pivot, circular irrigator for a farm that covers 25 acres. a.) how long is the irrigation boom (in feet) from the center pivot to its farthest extent? b.) if the irrigation boom makes 4 full revolutions in a day, how many miles does the end of the boom travel in 5 days?