One model of Earth’s population growth is p(t)=64/(1+11e^-0.8t), where t is measured in billons of people. Which of the following statements are true?
A. The population of Earth will grow exponentially for a while but then start to decrease.
B. The carrying capacity of Earth is 64 billion people.
C. The population of Earth is growing at a rate of just under 8% per year
D. In 1991, there were 5.74 billion people, according to the model