A child, who is 45 m from the bank of a river, is being carried helplessly downstream by the river’s

A child, who is 45 m from the bank of a
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 (Fig. 3-50). 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?