In the expansion of $(2+x)^n$, if the coefficients of the $5$th and $6$th terms are equal, then $n$ equals —

Question

Accepted Answer

$14$

Answer

$9$

Answer

$10$

Answer

$12$

In the expansion of (2+x)n(2+x)^n(2+x)n, if the coefficients of the 555th and 666th terms are equal, then nnn equals —