For Mexican American infants born in Arizona in 1986 and 1987, the probability that a child's gestational age is less than 37 weeks is 0.142 and the probability that his or her birth weight is less than 2500 grams is 0.051. Furthermore, the probability that these two events occur simultaneously is 0.031.

1. Let A be the event that an infant gestational age is less than 37 weeks and B the event that the infant's birth weight is less than 2500 grams. Are A and B independent events? Please provide an explanation.

a. No

b. Yes

2. For a randomly selected Mexican American newborn, what is the probability that A or B occur(s)? Please provide an explanation.

a. 0.261

b. 0.175

c. 0.162

d. 0.114

3. What is the probability that event A occurs given that event B occurs? Please provide an explanation.

a. 0.761

b 0.905

c. 0.608

d. 0.123