Need help on this question!!

Evaluate cos2θ for cosθ = square root of 3/2

Mario is constructing a frame for 10 in. by 8 in. photo. he wants the frame to be the same with all the way around in the same area of the frame and photo to be 120 square inches what is the dimension of the frame?

The random variable x is defined as the number marking the sector in which the arrow lands when the spinner in the diagram is spun once.