Can someone please help me with this?!

Suppose the radius of a circle is 16. what issuppose the radius of a circle is 16. what is its circumference its circumference

Ill mark the brainliest if you me with the these three questions 7,8,9

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 .