posted by Christina .
Sheena can row a boat at 2.90 mi/h in still water. She needs to cross a river that is 1.22 mi wide with a current flowing at 1.55 mi/h. Not having her calculator ready, she guesses that to go straight across, she should head 60.0° upstream.
(a) What is her speed with respect to the starting point on the bank?
(b) How long does it take her to cross the river?
(c) How far upstream or downstream from her starting point will she reach the opposite bank?
(d) In order to go straight across, what angle upstream should she have headed?