Willis has noticed that when time has been one of the variables analyzed by a scatterplot he has looked at, it has always been the independent variable. he has hypothesized that time can never be a dependent variable. does the scatterplot below confirm or invalidate willis's hypothesis?

Which expresions are equivalent to the one below? check all that apply. 5x

Describe the possible echelon forms of the standard matrix for a linear transformation t where t: set of real numbers is onto.

Aswimming pool has an input pump for filling the pool and an output pump for emptying the pool. the input pump can fill the pool in 3 hours, and the output pump can drain the pool in 5 hours. as you go to bed, the pool is full, but a neighbor’s kid turns on the output pump. at midnight, you awake to find the pool half empty. immediately, you turn on the input pump, but you are sleepy and forget to turn off the output pump. at what time will the pool become full?