In 2000 the deer population in NJ was 35000. In 2015 that number decreased to 21000. If the population can be modeled with an exponential decay model, what is the rate at which the population is decreasing?

just plug in the numbers, assuming

p(t) = ae^kt
p(0) = 35000, so a = 35000
p(15) = 35000 e^15k = 21000, so k = -0.034

p(t) = 35000 e^-.034t

e^-.034 = 0.9665, so the population is decreasing by 3.35% per year