For each of the following explain what permissions are granted. A file with: $[4$ marks$]$

$4\mathrm{.}1777$ permissions $4\mathrm{.}2655$ permissions $4\mathrm{.}3455$ permissions

$5.$ In the previous question which permission is the riskiest $$ why? Which of the above permission is safest $$ why? $[1$ mark$]$