Answer for all of them

What is the value of  y  in the solution to the system of equations? x  +  y  =  12x  –  3y  =  –30a. –8b. –3c. 3d. 8

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.

Griffin ordered a pair of sneakers online. he had a $22 credit that he applied toward the purchase, and then he used a credit card to pay for the rest of the cost. if the shoes cost $58, how much did griffin charge to his credit card when he bought the sneakers?