Exercise 6.28 mentioned that in the United States, birth weight of boys is approximately normal, with mean 3.41 kg and standard deviation 0.55 kg. For girls, the birth weight is also approximately normal with mean 3.29 kg and standard deviation 0.52 kg.
a. A weight below 2.5 kg is considered low birth weight. 2.5 kg corresponds to which percentile for boys and to which percentile for girls?
b. Is a birth weight of 2.5 kg more extreme for boys or girls? Why?