Number three I'm 95% sure.
I would say the best answer is B. Asking the learner to begin working on a problem.
When most people in Africa has aids, its considered an epidemic. When most people are considered fat asfack in the US its also considered and epidemic.
It would take 18 days, because it takes 3,500 calories to gain a pound, 3500/200 is 17.5, round that up to 18.
Answer:
Vaccines have been around since 1796 preventing people from diseases and decreasing death rates. I believe due to the modern vaccines and medicine people have been living longer than life expectancies in the 1700's and 1800’s, which was between 30 and 40 years. Vaccines train the human body to recognize viruses or bacteria and the antigens (molecule capable of inducing an immune response) will start attacking the virus or bacteria before it tries to spread and cause sickness once it is has recognized it. However, vaccines are not always 100% safe because they can come with side effects. For example, the Hepatitis B vaccine had a severe allergic reaction, called anaphylaxis which caused difficulty breathing, dizziness, and skin rashes for a few people.
