$P-V$ plots for two gases during an adiabatic process are shown in the figure. Plots $1$ and $2$ should correspond respectively to

The mean of four observations is $3$. If the sum of the squares of these observations is $48$,then their standard deviation is

If the unit of length and force be increased four times,then the unit of energy is

If the equilibrium constant for the reaction,$H_{2(g)} + I_{2(g)} \rightleftharpoons 2 HI_{(g)}$ is $K$,what is the equilibrium constant of $HI_{(g)} \rightleftharpoons \frac{1}{2} H_{2(g)} + \frac{1}{2} I_{2(g)}$?

The sum of the last eight coefficients in the expansion of $(1 + x)^{15}$ is:

Given below are two statements:-
Statement-$I$: Morphine is a narcotic analgesic. It helps in relieving pain without producing sleep.
Statement-$II$: Morphine and its derivatives are obtained from opium poppy.
In the light of the above statements,choose the correct answer from the options given below.