A horizontal force \(F_{\text {slide }}\) is exerted on a \(5.0-\mathrm{kg}\) box sliding on a polished floor. As the box moves, the magnitude of \(F_{\text {slide }}\) increases smoothly from 0 to \(5.0 \mathrm{~N}\) in \(5.0 \mathrm{~s}\). What is the box's speed at \(t=5.0 \mathrm{~s}(a)\) if it starts from rest and (b) if at \(t=0\) it has a velocity of \(3.0 \mathrm{~m} / \mathrm{s}\) in the direction opposite the direction of \(F_{\text {slide? }}\) ? Ignore any friction between the box and the floor.