Chapter 5.1, Problem 21E

Eastern Pacific Yellowfin Tuna Studies to fit a logistic model to the Eastern Pacific yellowfin tuna population have yielded

$N=\frac{148}{1+36e^{-2.61t}}$

where $t$ is measured in years and $N$ is measured in thousands of tons of fish.

a. What is the $r$ value for the Eastern Pacific yellowfin tuna?

b. What is the carrying capacity $K$ for the Eastern Pacific yellowfin tuna?

c. What is the optimum yield level?

d. Use your calculator to graph $N$ versus $t$.

e. At what time was the population growing the most rapidly?