Can someone plz me with problems 1-6

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?

Which of the following pair(s) of circles have las a common external tangent? select all that apply. a and b a and c b and c

Which equation could represent the relationship shown in the scatter plot? y=−3x−2 y=−3/4x+10 y=−2/3x+1 y=9x−12 scatter plot with x axis labeled variable x and y axis labeled variable y. points go from upper left to lower right.