An atom has $2$ electrons in $K$ shell,$8$ electrons in $L$ shell and $6$ electrons in $M$ shell. The number of $s$-electrons present in that element is

Match the columns and choose the correct option:

Column-$I$	Column-$II$
$(a)$ $4s$	$(p)$ Circular orbit around nucleus
$(b)$ $4p$	$(q)$ Non-directional orbital
$(c)$ $1s$	$(r)$ Angular momentum $= 2h/\pi$
$(d)$ $3d$	$(s)$ Radial node is zero

Assertion :- In $H$-atom,the energy of $3d$-level is smaller than $4s$-level.
Reason :- In multi-electron species,an orbital with lower value of $(n+\ell)$ has energy smaller than the orbital with larger value of $(n+\ell)$.

The orbital having two radial as well as two angular nodes is

The set of quantum numbers $n = 3$,$l = 0$,$m = 0$,$s = -1/2$ belongs to the element

The maximum probability of finding an electron in the $d_{xy}$ orbital is