1. Derek adds water to a pool at a rate of 12 gallons per minute and then reduces the
rate to 8 gallons per minute. Derek adds water to the pool for a total of 2 hours. Lett
be the time in hours that he adds water to the pool at the faster rate. Write algebraic
expressions to represent how many minutes he adds water to the pool at each rate.

Acertain standardized? test's math scores have a? bell-shaped distribution with a mean of 520 and a standard deviation of 105. complete parts? (a) through? (c)

Determine whether the following statements are true and give an explanation or counterexample. bold a. when using the shell method, the axis of the cylindrical shells is parallel to the axis of revolution. bold b. if a region is revolved about the y-axis, then the shell method must be used. bold c. if a region is revolved about the x-axis, then in principle it is possible to use the disk/washer method and integrate with respect to x or the shell method and integrate with respect to y.

How many $20 bills do you need to have to make $280