Determine the SCS time of concentration of a 400-ft by 400-ft asphalt parking lot (in minutes). A V-shaped channel (n-0.013)cuts the parking lot in half and picks up runoff from both sides equally. The channel has side slopes of 4H:1V and a longitudinal slope of 0.5%. Assume a depth of flow of 6-inches. The parking lot slopes at 1% toward the channel from both sides, and the 2-year, 24-hour rainfall is 2in.