4. A pool contained 32 gallons of water thirty minutes after it began to rain. Twenty minutes later (fifty minutes after the rain began to fall), the pool contained 40 gallons of water. Assume it rained at a constant rate (in gallons per minute). a) Determine the equation of the linear relation (in slope-intercept form) with x = the # of minutes it had been raining, and y = the # of gallons of water in pool. Sketch the graph. b) What do the slope and the y-intercept of your line indicate? c) Use your equation to determine how much water the pool will contain two hours after the rain began to fall. d) Use your equation to determine when the pool will overflow (the pool holds up to 100 gallons).