Answer:
[tex]d(t)=-108*t-3.5[/tex].
435.5 meters below water surface.
Step-by-step explanation:
We have been given that from an elevation of 3.5 m below the surface of the water. A northern bottle nose whale dives at a rate of 1.8 m/s.
Let us convert whale's dive rate in terms of meters per minute.
Since we know that 1 minute=60 seconds so we will multiply whale's dive rate by 60 to convert it in meters per minute.
[tex]1.8\frac{\text{meters}}{\text{second}} =1.8*60\frac{\text{meters}}{\text{minute}}[/tex]
[tex]108\frac{\text{meters}}{\text{minute}}[/tex]
We can write a rule that gives the whale's depth d as a function of time in minutes as:
[tex]d(t)=-108t-3.5[/tex]
Therefore, our function will be [tex]d(t)=-108*t-3.5[/tex].
Now let us find whale's depth after 4 minutes by substituting t=4 in our function.
[tex]d(4)=-108*4-3.5[/tex]
[tex]d(4)=-432-3.5[/tex]
[tex]d(4)=-435.5[/tex]
Therefore, after 4 minutes whale will be 435.5 meters below water surface.