Which of the following statements is incorrect?

In the reaction $LiH + AlH_3 \rightarrow LiAlH_4$,$AlH_3$ and $LiH$ act as

$A$ large open tank has two holes in the wall. One is a square hole of side $L$ at a depth $y$ from the top and the other is a circular hole of radius $R$ at a depth $4y$ from the top. When the tank is completely filled with water,the quantities of water flowing out per second from both the holes are the same. Then $R$ is equal to

If $y=(1+x)(1+x^2)(1+x^4) \dots (1+x^{2^n})$,then $(\frac{dy}{dx})_{x=0}$ is equal to

$A$ ball is falling freely from a height. When it reaches $10 ~m$ height from the ground,its velocity is $v_0$. It collides with the ground,loses $50 \%$ of its energy,and rises back to a height of $10 ~m$. Then the velocity $v_0$ is (in $~m/s$)

In the figure shown,the power generated in $y$ is maximum when $y = 5\,\Omega$. Then $R$ is .............. $\Omega$.