39-(15z+48)/27=35 what is z

One line passes through (-7,-4) and (5,4) . another line passes through the point (-4,6) and (6,-9)

How far could you drive on 50 gallons of gas

Carl's candies has determined that a candy bar measuring 3 inches long has a z-score of +1 and a candy bar measuring 3.75 inches long has a z-score of +2. what is the standard deviation of the length of candy bars produced at carl's candies?