This is reaally long. But I need help. I need the most help with word problems!!

Domingo decides to ride the ferris wheel at the carnival. When he gets into a seat that is at the bottom of the ferris wheel, he is 4 ft above the ground.

a. if the radius of the ferris wheel is 36 feet, how far above the ground will Domingo be when his seat reaches the top?

b. the ferris wheel rotates 300 degrees counterclockwise and stops to let other passengers on the ride. How far is Domingo when he stops?

c. suppose the radius of the ferris wheel is only 30 ft how far above the ground is Domingo after the ferris wheel rotates 300 degrees

d. suppose the radius of the ferris wheel is r. write an expression for the distance from the ground to Domingo after the ferris wheel rotates 300 degrees.

please help me do this , step by step would be nice.

thanks in advance!!