Can someone please explain to me how to solve this and problems like this in the easiest way possible

What is sin 7x/4 ? i need on this urgent trig

For the following geometric sequence, find the recursive formula. {-80, 20, -5, } i need : ')

Abird on top of a 200 ft bridge tower sees a man standing on the lower part of the bridge (which is 50 ft above the ground). the angle of depression from the bird is 26 ̊. how far is the man from the base of the bridge tower? with explanation and pictures .