Suppose that we have a B$+-$ tree and the size of the search key field V is equal to $10$ bytes, the size of the data $($record$)$ pointer Pr $=6$ bytes, and the tree $($block$)$ pointer P is $5$ bytes and the value of p $($the order or the maximum number of a tree pointers in a node$)$ is equal to $20$ for an internal node.

a$)$ Calculate the block size $($B$)$

b$)$ Suppose that we have a B$-$ tree instead of B$+-$ and based on the block size found in question $($a$),$ calculate the order $($p$)$ for an internal node in this case.