Deep draws the spiral of irrational numbers below on a paper.

What is the length of $OE$ in the spiral?

Simplify: $\frac{1}{-4-\sqrt{15}}$

Two persons started from a common point $\left(0,0\right)$ in the figure below, with the same speed. One person $\left(X\right)$ went along a straight line path to $P$, which is $25 \mathrm{m}$ East and $32 \mathrm{km}$ North.  The second person $\left(Y\right)$ went due East. 

To which of these positions person $Y$ will be the closest when person $\left(X\right)$ is at $P$?

If $\frac{\sqrt{7}+2\sqrt{3}}{2\sqrt{7}-\sqrt{5}}=\frac{c+\sqrt{p}+\sqrt{q}+\sqrt{r}}{23} \left(p<q<r\right)$ where $p, q, r$ are rational numbers, then $q+r-p=$

If $x=\frac{1}{3+2\sqrt{2}}$, then the value of $x-\frac{1}{x}$ is