A river flows due east at 1.51 m/s. A boat crosses the river from the south shore to the north shore by maintaining a constant velocity of 10.8 m/s due north relative to the water. (a) What is the velocity of the boat as viewed by an observer on the shore? m/s at ° east of north (b) If the river is 301 m wide, how far downstream is the boat when it reaches the north shore?