Q$2.$ A bracket $A$ is used to support a hanger under a centrally applied force of $30$ kN as shown. The thickness of the bracket and hanger are both $20$ cm $.$ Determine the minimum required dimensions of $h,b,$ and $t$ in order for the safety of the bracket and the hanger. The materials' properties are listed in the table.

$[10$ marks$]$

$\backslash$table$[[,{}_u,{}_u,$Factor of Safety$],[$Bracket$,350$ MPa,$220$ MPa,$3],[$Hanger$,400$ MPa,$180$ MPa$]]$