6.7.8 need help !

6. Use the Fundamental Theorem of Calculus to find d (x t dx Jo t2 sin(2t) dt 4 pts 7. Evaluate the integral in terms of geometry, sketch graphs to illustrate your answer. 8 pts 3 + 2x + 149 - x2 dx 8. Suppose w'(t) represents the rate of weight gain of a child in pounds per year. Assume Is w'(t ) dt = 35 4 pts a. What does S w'(t) dt represent? b. If a child weighed 45 pounds at age 5, how much does it weight at age 10