[بحر*]

السلام عليكم و رحمة الله و بركاته ، هاا سؤال انا حليت جزء منه و الجزء الأخير مب متأكده منه فممكن مساعده
في Potential Energy

A 10.0 Kg block is released from point A in the figure below. The block travels along a smooth frictionless track except for the rough 1 m long portion between points B and C. At the end of the track, the 10 kg block hits a spring of force constant (k) = 2000 N/m, and compresses the spring a distance of 20 cm from its equilibrium position before coming to rest momentarily.
a) What is the speed of the block at point B?
b) What is the speed of the block at point C?
c) What is the value of the coefficient of kinetic friction (k) between the block and the rough portion between points B and C?