Pls tell me what it is

Acircle has a circumference of 28.36 units what is the diameter of the circle

Aflagpole broke in a storm. it was originally 8 1 81 feet tall. 2 8 28 feet are still sticking straight out of the ground, where it snapped, but the remaining piece has hinged over and touches the ground some distance away. how far away is the end of the pole from the base of the pole along the ground?

Yvaries directly as x. y =90 when x=6. find y when x=13