A 5.8 kg mass is attached to a spring with a stiffness of 490 N/m and is allowed to move along a friction-less horizontal surface. The mass is pulled back so that the spring is stretched 0.19 m from its equilibrium position. What will be the speed of the mass in m/s as it returns to the equilibrium position?

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.