$m$ and $n$ are two positive integers satisfying $1<m<n\le 40.$ Find the number of pairs of $(m, n)$ such that their product $mn$ is divisible by $33.$

If $P713$ is divisible by $11$, find the value of the smallest natural number $P$?

How many numbers are there from $14$ to $159$ which are divisible by both $2$ and $8$?

Consider the following statements: For any integer $n,$ 

I.. $n^2+3$ is never divisible by $17$ .

II.. $n^2+4$ is never divisible by $17$. Then