3. The histogram displays the number of 2008 births among U.S. women ages 10 to 50. Each bin represents an interval with a class width of two years, and the height of each bin represents the frequency with which the data fall within that interval. Use the histogram to answer parts (a), (b), and (c). Births by mother's use (2008) - Fmpency of births (in Wands) lo 20 M's age (in years) (a) Identify the cases and variables of this study. (b) How many births occurred among women who are at least 38 years old? (c) What percentage of births occurred among women between the ages of 16 to 18 (not including 18-year-olds)? Round off your answer to 2 decimal places