She begins at sea level, which is an elevation of 0 feet.
She travels straight down for 41 seconds at a speed of 4.9 feet per second.
She then ascends for 49 seconds at a speed of 3.2 feet per second.
After this 90-second period, how much time, in seconds, will it take for the scientist to travel back to sea level at 3.6 feet per second?