A 1.30 kg mass on a spring oscilates horizontally with little friction according to the following equation: x = 0.070cos(2.50t), where x is in meters and t in seconds.
1) Find the maximum energy stored in the spring during an oscillation.
2) Find the maximum velocity of the mass.
I have no clue how to do this problem. Can someone show me step by step how to do it.