A block of mass m=10 kg at rest slides down a rough incline plane of θ=30° and length l=5 m. The coefficient of kinetic friction between the block and the incline is μ_k=0.1. At the bottom of the plane the block continues to slide on a frictionless surface and hits a spring with spring constant k=100 N/m.
(a) Calculate the speed of the block at the point B of the incline.
(b) Calculate the maximum compression distance of the spring d, the box needs to stop after hitting the spring.