What is the standard deviation of the following series?

Class	$0-10$	$10-20$	$20-30$	$30-40$
Freq	$1$	$3$	$4$	$2$

Which one of the following is not considered as part of the endomembrane system?

Power supplied to a particle of mass $2 \ kg$ varies with time as $P = \frac{3t^2}{2} \ W$. Here,$t$ is in $s$. If the velocity of the particle at $t = 0$ is $v = 0$,the velocity of the particle at time $t = 2 \ s$ will be ............. $m/s$.

Solar radiation emitted by the sun resembles that emitted by a black body at a temperature of $6000\, K$. Maximum intensity is emitted at a wavelength of about $4800\, \mathring{A}$. If the sun was cooled down from $6000\, K$ to $3000\, K$,then the peak intensity would occur at a wavelength of ......... $\mathring{A}$.

The major product in the following reaction is:

If $x^2+2px-2p+8>0$ for all real values of $x$,then the set of all possible values of $p$ is