Venn diagrams for statistics! I just need to do 3, so if someone could explain it that would be great!

This is the number of parts out of 100, the numerator of a fraction where the denominator is 100. submit

Assume that adults have iq scores that are normally distributed with a mean of mu equals 100 and a standard deviation sigma equals 20. find the probability that a randomly selected adult has an iq between 80 and 120.assume that adults have iq scores that are normally distributed with a mean of mu equals 100 and a standard deviation sigma equals 20. find the probability that a randomly selected adult has an iq between 80 and 120.

Find the area of the shaded region.