9. A boat heads due east across a 100. m-wide stream with a velocity of 20.0 m/s. The stream is flowing from north to south at a rate of 5.00 m/s. a) What is the resultant velocity of the boat? b) How long does it take the boat to reach the other side? c) How far downstream is the boat when it reaches the other side? d) In which direction should the boat head in order to end up directly across the stream?