A city employee paints curbs in parking lots and replaces road signs. It takes 0. hour to paint a parking lot curb and 2.5 hours to replace a road sign. The function below can be used to find c, the number of parking lot curbs the employee paints when he replaces croad signs in a 40-hour workweek. C = 40 - 2.5 0.5 If the employee painted 20 curbs in one week, how many road signs did he replace that week?