"A scientist uses a submarine to study ocean life. She begins at sea level, which is an elevation of 0 feet. She travels straight 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 to sea level at the submarine's maximum speed of 4.8 feet per second? Round your answer to the nearest tenth of a second." I need this done soon, please help.

Respuesta :

It will take 51.9 seconds to return to sea level.

What is speed?

The rate of change of position of an object in any direction. Speed is measured as the ratio of distance to the time in which the distance was covered.

Using the speed - distance relationship, the time taken for the scientist to travel back to sea level would be 51.9 seconds

Distance = Speed × time

First travel :

Distance covered = 90 × 3.5 = 315 feet

Second travel :

Distance covered = 30 × 2.2 = 66 feet

Net change in position from sea level :

(315 - 66) feet = 249 feet

Maximum speed = 4.8 feet per second

Time taken = Distance / speed

Time taken = 249 ÷ 4.8 = 51.875 seconds

Hence, it will take 51.9 seconds to return to sea level.

Learn more about speed, here:

brainly.com/question/14375199

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