Find the value of x. 12.5, -10, -7.5, x; the mean is 11.5

In the diagram, a building cast a 35-ft shadow and a flagpole casts an 8-ft shadow. if the the flagpole is 18 ft tall, how tall is the building? round the the nearest tenth.

What is the area of the shaded sector?

You eat $0.85 for every cup of hot chocolate you sell. how many cups do you need to sell to earn $55.25