Final answer:
The average rate of change of the elephant population in Kenya over the last 10 years is -12,000 elephants per year.
Step-by-step explanation:
The average rate of change can be calculated by finding the change in the elephant population over a given time period and dividing it by the number of years. In this case, the population dropped from 150,000 to 30,000 over 10 years. To find the change, subtract the initial population from the final population: 30,000 - 150,000 = -120,000. Divide this by the number of years: -120,000 / 10 = -12,000. Therefore, the average rate of change is -12,000 elephants per year.