$7\mathrm{.}2$ Write an Insertion Sort algorithm for integer key values. However, here's the catch: The input is a stack $($not an array$),$ and the only variables that your algorithm may use are a fixed number of integers and a fixed number of stacks. The algorithm should return a stack containing the records in sorted order $($with the least value being at the top of the stack$).$ Your algorithm should be $($n$^2)$ in the worst case.