How to calculate the net force required for the system of pulleys to move at a given acceleration?

Figure shows a system of 3 blocks of 5 kg mass each. Find the value of external force F required to move the block A at acceleration $5$m/${s}^{2}$. Take all surfaces smooth and g = $10 m$/$s 2$

$200 N$
here the pulley on the mass $A$ also applies force of $T$ on horizontal as well as vertical direction as shown.