A platypus foraging for prey can detect an electric field as small as 0.002 N/C. Part A To give an idea of sensitivity of the platypus's electric sense, how far from a 50nC point charge does the field have this magnitude

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.