What conditions must be met if a man-made satellite is to attain a circular orbit around the earth? (choose as many as apply)
a) it must be launched with a tangential speed of 0.
b) it must be launched with a tangential speed of 8 km/s.
c) it must be launched with a tangential speed greater than 8 km/s.
d) it must be launched horizontally at a distance over 150 kilometers above the earth.
e) it must be launched vertically with a speed of 8 km/s.

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.