A big ship drops its anchor. E(t) models the anchor's elevation relative to the water's surface (in meters) as a function of time t (in seconds). E(t)=−2.4t+75 How far does the anchor drop every 5 seconds?

Plug in 5 for t, while ignoring the +75.
[tex]2.4(5) = 12[/tex]
Therefore, the anchor drops 12 m. every 5 seconds