A student uses a submarine to study ocean life. She begins at sea level, which is at an elevation of 0 feet. She travels down for 90 seconds at a speed of 3.5 feet per second. She then travels directly up for 30 seconds at a speed of 2.2 feet per second. After this 120-second period, how much time, in seconds, will it take for the scientist to travel back up to sea level at the submarines maximum speed of 4.8 feet per second
