The area of a rectangular field is$1120 \;m^2 $. Its length is $40 \;m$. Find the cost of fencing the boundary of the field at the rate of $Rs. 3.20 \;/m^2$

Question

$\begin{array}{1 1} Rs. 432 \\ Rs. 436 \\ Rs. 435.20 \\ Rs. 445.20 \end{array} $