Martina wants to canoe on the Lamine River 24 km upstream and 36 km downstream. Her rate in still water is 15 km per hour. The time (in hours) it takes to go upstream is given by the expression and the time it takes to go downstream is, where x is the speed of the current in km per hour. Find the ratio of time it takes for Martina to go upstream to the time it takes Martina to go downstream in simplified form. Could the speed of the current be 15 km per hour? Explain. If it takes Martina the same amount of time to go upstream as it does for her to godownstream, what is the speed of the current? How long does it take Martina to go upstream anddownstream?