Show that the differential form in the integral below is exact. Then evaluate the integral.\\
$\int_{(0,0,0)}^{(3,6,-4)} 20x dx + 16y dy + 20z dz$\\
Select the correct choice below and fill in any answer boxes within your choice.\\
A. $\int_{(0,0,0)}^{(3,6,-4)} 20x dx + 16y dy + 20z dz = $\\
(Simplify your answer. Type an exact answer.)\\B. The differential form is not exact.