7. [12 marks] a. (6 marks) Use part 1 of the Fundamental Theorem of Calculus and the chain rule to differentiate the following integral. You must show the step where you use part 1 of the FTC and the step where you use the chain rule. t In(4 + 3t) dt b. (6 marks) Use the comparison properties of integrals from section 5.2 of the textbook to show 4