Pollution begins to enter a lake at time t= 0 at a rate (in gallons per hour) given by the formula f(t), where t is the time (in hours). At the same time, a pollution filter begins to remove the pollution at a rate g(t) as long as the pollution remains in the lake. ((1) = 9(1 - e -0.51), g(1) = 0.4t a. How much pollution is in the lake after 10 hours? The amount of pollution that remains in the lake after 10 hours is gallons. (Do not round until the final answer. Then round to the nearest hundredth as needed.) b. Use a graphing calculator to find the time after 1 = 0 when the rate that pollution enters the lake equals the rate the pollution is removed. The rate of pollution entering equals the rate of the pollution being removed after hours. (Round to the nearest whole number as needed.) c. Find the amount of pollution in the lake at the time found in part b. The amount of pollution in the lake after 22 hours is approximately gallons. (Do not round until the final answer. Then round to the nearest hundredth as needed.) d. Use a graphing calculator to find the time when all the pollution has been removed from the lake. The time when all the pollution has been removed from the lake is hours. (Round to the nearest hundredth as needed.)