Example Package Design A company uses a box with a square base and an open top for a bath assortment $($see figure$).$ If $x$ is the length $($in inches$)$ of each side of the base and $y$ is the height $($in inches$).$

a$)$ Find the total amount of material $M(x,y)$ required to construct one of these boxes, and evaluate $M(5,10)$

b$)$ Find the volume $V(x,y)$ and evaluate $V(5,10).$