The length of a rectangle is increasing at a rate of $7c\frac{m}{s}$ and its width is increasing at a rate of $3c\frac{m}{s}.$ When the length is $9cm$ and the width is $5cm,$ how fast is the area of the rectangle increasing

$($in $c\frac{m^2}{s})?$

$c\frac{m^2}{s}$