What is the sum of (–2.1x + 3.7) and (5 + 4.9x)? A.) -7.0x + 8.7

B.) -2.8x + 8.7

C.) 2.8x + 8.7

D.) 7.0x + 8.7

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.