Step $3$

Therefore, we have the following.

$M_4=2[(\sqrt[\phantom{2}]{3+2})+(\sqrt[\phantom{2}]{3^3+2})+(\sqrt[\phantom{2}]{3^3+2})+(\sqrt[\phantom{2}]{3^3+2})]$

$=(roundedto$ four decimal places$)$

SKIP $($YOU CANNOT COME BACK$)$