The starter motor of a car engine draws an electric current of 20.0 A from the battery. The copper wire to the motor is 5.90 mm in diameter and 1.57 m long. The starter motor runs for 0.65 s before the car engine starts up. How much electric charge passes through the starter motor

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.