Pls help this is iready and I need to finish now

It takes a total of 6 hours to fill up an inground backyard pool using a standard house. a function can represent this situation to represent the amount of water in the pool until it is full a function of time the hose is running. determine the domain for the function

Scrub a dub toothbrushes are $4.00 each. there is a 10% discount, but there is also a 6% sales tax after the discount is applied. what is the new price after tax? round to the nearest penny

Find the domain of the following expression: 1/(√x)-2