Yan is climbing down a ladder. each time he descends 4 rungs on the ladder, he stopped to see how much farther he has to go. if yan made eight stops with no extra steps, which expression best shows another way to write the product of the number of ladder rungs that yan and climbed?

4+4+4+4
8+8+8+8
(-1)(4+4+4+4)
(-8) + (-8) + (-8) + (-8)

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?

Precalculus question, image attached.

Which spreadsheet would be used to compute the first nine terms of the geometric sequence a^n=32•(1/2)n-1