If w'(t) is the rate of growth of a child in pounds per year, what does O The child's weight at age 5. O The child's weight at age 13. 13 row'(t) dt w'(t) dt represent? O The change in the child's weight (in pounds) between the ages of 5 and 13. O The child's initial weight at birth. O The change in the child's age (in years) between the ages of 5 and 13.