Question

A submarine can descend at a rate of -2.5 meters/second. Suppose that the submarine begins at a depth of -25 meters.

Answer 1

The distance from the initial depth to the maximum depth is:
abs (-200- (-25))= 175 m (distance is always >=0, so we have to take the abs).

175 m* (1 sec/ 2.5m)= 70 sec.

It would take the submarine 70 seconds to reach its maximum depth.

Hope this helps~