$\frac{d}{dx}(\sin 30^\circ)$ is equal to

What is the value of $\alpha$ if $\alpha = \frac{25}{50}$?

$\frac{d}{dx}\left( \frac{1}{x^4 \sec x} \right) = $

${d \over {dx}}({x^2}{e^x}\sin x) = $

The side of a square is increasing at the rate of $0.2\,cm/s$. The rate of increase of perimeter with respect to time is $...........\,cm/s$.

If $F = \frac{2}{\sin \theta + \sqrt{3} \cos \theta}$,then the minimum value of $F$ is