A boat takes 2 hours to go 4 miles upstream. It can go 8 miles downstream in the same time. Find the rate of the current and the rate of the boat in still water.(Hint: Because the current pushes the boat when it is goingdownstream, the rate of the boat downstream is the sum of the rate of the boat and the rate of the current. The current slows down the boat when it is goingupstream, so the rate of the boat upstream is the difference of the rate of the boat and the rate of thecurrent.)