In the number 3,287,854 how many times greater is the value of the 8 in the ten thousands place compared to the value of the 8 in the hundreds place?

How do i work this problem out using the equation a=pe^rt

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 inequality comparing two of the expressions is true when 0.7 < x < 0.9