2 Suppose that water is being pumped into an initially empty tank (see FigiP12.32). It is known that the rate of flow of water into the tank at u(in seconds)

is 50 -t 1/s. The amount of water Q that flows into the tduring the first x seconds can be shown to be equal to the integral of dexpression (50 - 1) evaluated from 0 to x seconds*