Please answer the question below

The rate of change in the submarine's elevation is 26.0 feet per second.

Step-by-step explanation:

She begins 151 feet below sea level

Thus, her initial point is y₁ = 151 feet below sea level

i.e. at t₁=0 seconds, y₁ = 151 feet below sea level

After descending for the 3 seconds, she is 229 feet below sea level.

Thus, her second point is y₂ = 229 feet below sea level after 3 seconds

i.e. at t₂=3 seconds, y₂ = 229 feet below sea level

The rate of change is basically the slope. Thus, the rate of change can be obtained by taking the slope.

slope = rate of change = (y₂ - y₁)/(t₂ - t₁)

                                      = (229 - 151) / (3 - 0)

                                       = 78/3

                                       = 26.0

Therefore, the rate of change in the submarine's elevation is 26.0 feet per second.