Please give me the correct answer. T^T

Which of the following expressions is equal to 2x^2+8

Cd is the perpendicular bisector of both xy and st, and cy=20. find xy.

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?