choose correct answer & explain why

Conventional cyclone cleans particle$-$laden air of flow rate of $10$ m$3/$second$.$ Determine actual power required $($in KW$)$ if the Pressure drop of $1000$ pa and the fan used for pumping has $50\%$ efficiency $?$

$1.10$

$2.$ Connot determined

$3.40$

$4.20$