http://www.nzqa.govt.nz/nqfdocs/ncea...286-exm-08.pdf

Is anybody able to help me with questions:
4, 5, 6a, and 7?

If possible, could you explain the working?
I understand the basic rules of differentiation and integration, however, I'm unable to apply these to the above questions, and can't make sense of what 4 is asking.

Thanks!