Two boats start together and race across a 68 km wide lake and back. Boat A goes across at 68 km/h and returns at 68 km/h. Boat B goes across at 34 km/h, and it crew, realizing how far behind it is getting, returns at 102 km/h. Turnaround times are negligible, and the boat that completes the round-trip first wins. Which boat wins and by how much? (Or is it a tie?)
(a) By how much? (Enter NONE if it was a tie.)
(b) What is the average velocity of the winning boat? (Enter NONE if it was a tie.)