a child who is 45 m from the bank river is being carried helplessly downstream by the river's swift current of 1.0 m/s.

a child who is 45 m from the bank river is being carried helplessly downstream by the river's swift current of 1.0 m/s. As the child passes a lifeguard on the river's bank, the lifeguard starts swimming in a straight line until she reaches the child at a point downstream. If the lifeguard can swim at a speed of 2.0 m/s relative to the water,, how long does it take her to reach the child? How far downstream does the lifeguard intercept the child?