Atree was 12 3/8 inches tall when it was first planted. three years later the tree was 21 1/8 inches tall how much did the tree grow in the 3 years?

Michael gose to a theme park and rides two different roller coasters that both begin on a raised platform his height while on the first roller coaster measured in feet from the platform height can be modeled by the following graph where t is the number of seconds since the ride began