First one should be:
(If you integrate with respects to x, which to me seems easier)
Sketch the regions enclosed by the given curves. Decide whether to integrate with respect to x or y. Draw a typical approximating rectangle and label its height and width.
I keep on getting 328/3 as my answer, but when I input it the answer is wrong. I solve the integral in terms of dy but I always get it wrong.
(d) Estimate the time t at which the cars are again side by side.
I keep on getting 2.2s but I input it and it ends up wrong.