It's for extra credit and i need suppose an 85 kg sky diver is falling toward the earth. when the skydiver is 25 m above the earth, he is moving 55m/s. at this point, calculate the sky divers gravitational potential energy. about 46,000 jabout 21,000 jabout 128,600jabout 116,900j

Asled is being held at rest on a slope that makes an angle θ with the horizontal. after the sled is released, it slidesa distance d1 down the slope and then covers the distance d2 alongthe horizontal terrain before stopping. find the coefficient ofkinetic friction μk between the sled and the ground, assumingthat it is constant throughout the trip. find the coefficient of kinetic frictionμk. express your answer in terms of someor all of the variables d1, d2, and θ.