A block $($mass $!=3\mathrm{.}0$ kg$),$ starting from rest at a height h$,$ slides down a frictionless ramp

and along a level frictionless surface before it collides, and sticks, to a second block $($mass $"=4\mathrm{.}0$ kg$).$

This second block is attached to a spring with spring constant of $252$ N$/$m$,$ which, in turn, is affixed to a

rigid wall at its other end. After this collision, the blocks compress the spring $0\mathrm{.}30$ meters before they

momentarily come to rest.

$($a$)$ What is the speed of the combined blocks $1$ and $2$ the instant after the collision?

$($b$)$ What is the speed of block $1$ the instant before it collides with block $2?$

$($c$)$ From what height h did the first block begin to slide down the ramp