Permutation Combination question bank (Maths)

Three persons enter in a lift at the ground floor. The lift will go upto $10^{\text {th }}$ floor. The number of ways, in which the three persons can exit the lift at three different floors, if the lift does not stop at first, second and third floors, is equal to $\_\_\_\_$.

The largest $\mathrm{n} \in \mathbf{N}$, for which $7^{\mathrm{n}}$ divides 101!, is :