The current in a wire varies with time according to the relationship $I=55 \mathrm{~A}-\left(0.65 \mathrm{~A} / \mathrm{s}^{2}\right) t^{2} .$ (a) How many coulombs of charge pass a cross section of the wire in the time interval between $t=0$ and $t=8.0 \mathrm{~s} ?(\mathrm{~b}) \mathrm{What}$ constant current would transport the same charge in the same time interval?