Can someone help me pls. this is a test pls show work

The perimeter of a movie screen is 54 meters. the screen is 18 meters wide. how tall is it?

If f(x) and g(x) are inverse functions of each other, which of the following shows the graph of f(g(x)

If the altitude is drawn to the hypotenuse of a right triangle, then the two triangles formed are similar to the original triangle and to each other. which set of triangles shows the similar triangles created by the altitude in the diagram?