A 68 g ice cube can slide without friction up and down a 30° slope. The ice cube is pressed against a spring at the bottom of the slope, compressing the spring 10 cm. The spring constant is 21N/m. When the ice cube is released, what total distance will it travel up the slope before reversing direction? The ice cube is replaced by a 68 g plastic cube whose coefficient of kinetic friction is 0.20. How far will the plastic cube travel up the slope?
A)0.70m,0.40m
B)0.75m,0.45m
C)0.80m,0.50m
D)0.85m,0.55m