Solve the Problem $\mathrm{E}=43.5 \mathrm{w}^{-0.61}$ , Where $\mathrm{w}$ Is the Weight of the Dolphin (In

Multiple Choice

Solve the problem.
-The energy cost of a speed burst as a function of the body weight of a dolphin is given by $\mathrm{E}=43.5 \mathrm{w}^{-0.61}$ , where $\mathrm{w}$ is the weight of the dolphin (in $\mathrm{kg}$ ) and $\mathrm{E}$ is the energy expenditure (in $\mathrm{kcal} / \mathrm{kg} / \mathrm{km}$ ) . Suppose that the weight of a $400-\mathrm{kg}$ dolphin is increasing at a rate of $8 \mathrm{~kg} / \mathrm{day}$ . Find the rate at which the energy expenditure is changing with respect to time.

A) $-0.0137 \mathrm{kcal} / \mathrm{kg} / \mathrm{km} /$ day
B) $-0.0017 \mathrm{kcal} / \mathrm{kg} / \mathrm{km} /$ day
C) $-5.491 \mathrm{kcal} / \mathrm{kg} / \mathrm{km} /$ day
D) $-20.5166 \mathrm{kcal} / \mathrm{kg} / \mathrm{km} /$ day