A Canadian study examined the pregnancy weight gain of underweight mothers, women who had been underweight before becoming pregnant. A Normal distribution with mean 36.6 lb and standard deviation 11.9 lb is a reasonable model for the distribution of pregnancy weight gains in this population.

a) Perform the appropriate computation and fill in the blank to complete this sentence in context: In this population, the first quartile of pregnancy weight gains is_____.

b) For underweight mothers, health organizations recommend a pregnancy weight gain between 27.5 lb and 39.5 lb. What is the probability that a randomly selected underweight mother in Canada would have a pregnancy weight gain in the recommended range?