write an expression for the rate of the water leaking out of the tank

Question

water is pumped into an underground tank at a constant rate of 8 gallons per minute. water leaks out of the tank at the rate of √t+1 gallons per minute, for 0≤t≤120 minutes. At time t=0, the tank contains 30 gallons of water.

Answer 1

water is pumped into at a constant rate of 8 gallons per minute, and water leaks out of the tank at the rate of √t+1 gallons per minute, for 0≤t≤120 minutes

So the rate of the water leaking out of the tank is -8 + √t+1, for 0≤t≤120 minutes