A $4-$m$-$long beam is loaded as shown. Determine the loading of an equivalent force$-$couple system at end $A$ of the beam that is equivalent to this loading shown in figure $b.$

$($b$)$

$300$ N

$($c$)$

$($e$)$

$(f)$

$(g)$

$($h$)$

Figure $($a$)$

$200$ N

$400$ N