The weight of a baby measured over an 11-month period is given in the weight chart below for this problem. Weight (lb) Age (months) 6.6 0 (birth) 7.4 1.0 9.6 2.0 11.2 3.0 12.0 4.0 13.6 5.0 13.8 6.0 14.8 7.0 15.0 8.0 16.6 9.0 17.5 10.0 18.4 11.0 (b) What was the average monthly weight gain for the baby over the period from 7 months to 10 months? (c) If a baby continued to grow at the same rate as in the first 3 months of life, what would the child weigh at age 9 years?