$P$ and $Q$ are two points observed from the top of a building $10\sqrt{3} m$ high. If the angles of depression of the points are complementary and $PQ=20 m$, then the distance of $P$ from the building is

$\frac{2+{\tan }^2 \mathrm{\theta }+{\cot }^2 \mathrm{\theta }}{\sec \mathrm{\theta cos} \mathrm{\theta }}$ is equal to:

The angle of elevation of top of tower from point $x$  and $y$  at  distance $m$ and  $n$ respectively from base of tower and in the same straight line with it are complementary. The height of tower is

Let $\mathrm{AB}$ represent a building of height $\mathrm{h} \mathrm{metre}$ with $\mathrm{A}$ being its top, $\mathrm{B}$ being its bottom. Let $\mathrm{A}\text{'}\mathrm{B}\text{'}$ represent a tower of height $(h+x) \mathrm{metre} (x>0)$with $\mathrm{A}\text{'}$ being its top and $\mathrm{B}\text{'}$ being its bottom. Let $\mathrm{BB}\text{'}=\mathrm{d} \mathrm{metre}$. Let the angle of elevation of $\mathrm{A}\text{'}$ as seen from $\mathrm{A}$ be $45°$.
Consider the following statements:
Statement I : $h+x>d$
Statement II : The angle of depression of $\mathrm{B}$ as seen from $\mathrm{A}\text{'}$ is less than $45°$.
Which one of the following is correct in respect of the above statements?

Raju (as an observe) is $1.8$ m tall and is $17.32$ m away from the base of a building .  The angel of elevation from his eye to the top of buliding is $30°$.

The height of building is