Using Figure $8\mathrm{.}14$ in the text, what is the fan efficiency for a fan that operates at $9000$ CFM @ $3\mathrm{.}6"$ H$2$O$?$ Select the closest answer.

Question $20$ options:

$1)$

$7\%$

$2)$

$50\%$

$3)$

$90\%$

$4)$

$70\%$