Statement 1 : In post-office box experiment, the battery key is pressed before the galvanometer key.

Statement 2 : In post-office box experiment, if galvanometer key is pressed first and then we press battery key, then galvanometer may get damage.

A metre bridge is set up as shown, to determine an unknown resistance $X$ using a standard $10 \mathrm{\Omega }$ resistor. The galvanometer shows null point when the tapping key is at $52 \mathrm{cm}$ mark. The end-corrections are $1 \mathrm{cm}$ and $2 \mathrm{cm}$ respectively for the ends $\mathrm{A}$ and $\mathrm{B}$. The determined value of $X$ is 

$1 \mathrm{cm}$ of the main scale of vernier calipers is divided into $10 \mathrm{divisions}$. The vernier scale had $n \mathrm{divisions}$, so that least count of the calipers is $0.005 \mathrm{cm}$. The value of $n$ is