What is the radius of a circle if the area is 78.5 cm^2

Which expression is equivalent to (3^2)^-2 a.-81 b.-12 c.1/81 d.1/12

There is an entrance to the computer room at point e which lies on ab and is 5 feet from point a. plot point e on the coordinate plane. find the distance from the entrance at point e to the printer at point e

In trapezoid abcd, ac is a diagonal and ∠abc≅∠acd. find ac if the lengths of the bases bc and ad are 12m and 27m respectively.