Which of the following amines undergoes acylation reaction?

If $|a|=1, |b|=2$ and the angle between $a$ and $b$ is $120^{\circ}$,then ${(a+3b) \times (3a-b)}^2$ is equal to

$\int_0^{\pi / 2} \frac{d x}{1+\tan ^3 x}$ is equal to :

The energy of an electromagnetic radiation is $19.875 \times 10^{-13} \ erg$. What is its wave number in $cm^{-1}$? $(h = 6.625 \times 10^{-27} \ erg \ sec, c = 3 \times 10^{10} \ cm \ sec^{-1})$

If $y$ is a function of $x$ and $\log(x+y)=2xy$,then the value of $y'(0)$ is

An increase in $CO_2$ concentration in the atmosphere will result in