Consider the following three statements:

1 $10p^2+1$ and $10p^2-1$ are both prime when $p$ is an odd prime.

2 Every prime greater than $5$ is of the form $6n+1$ for some integer $n$.

3 No multiple of $7$ greater than $7$ is prime.

The result $91=7\times 13$ can be used to provide a counterexample to which of the above statements?