Two electrons occupying the same orbital are distinguished by

$A$ thin prism $P_1$ with angle $4^o$ and made from a glass of refractive index $1.54$ is combined with another thin prism $P_2$ made from glass of refractive index $1.72$ to produce dispersion without deviation. The angle of the prism $P_2$ is.....$^o$

If vapour pressures of pure liquids $A$ and $B$ are $300 \ torr$ and $800 \ torr$ respectively at $25 \ ^oC$. When these two liquids are mixed at this temperature to form a solution in which mole percentage of $B$ is $92$,then the total vapour pressure is observed to be $0.95 \ atm$. Which of the following is true for this solution?

If the force is given by $F = at + bt^2$,where $t$ is time,the dimensions of $a$ and $b$ are:

What is the concentration of $20$ volume $H_2O_2$ in $g/L$?

In the ground state,an element has $13$ electrons in the $M$ shell. The element is