Problem: Bob has just graduated from medical school. He went on to serve his community. Especially he is interested in treating children. One day he saw two children, child M and child N, and found child M is infected with Acute Hepatitis B while child N is infected with Chronic Hepatitis B. Next day he saw two other children, child O and child P. Child O was younger, but child P was older. Did child N's illness occur within six months of exposure or the virus remained in his body?

A: virus remained in his body

Problem: Two teams of runners were training for a 10k. Team Y jogged early in the morning when the weather was cool. Team X started their training in the heat so many team members had problems sweating. Which team had fewer people that experienced fatigue?

A: Team Y

Problem: Tom and Jerry were two 50-year-olds which went to high-school together. They recently met and discussed their health problems over coffee. Tom had hypertension and the doc told him to change his diet. Which friend didn't have to start drinking skim milk?

A: Jerry

Problem: Dorothy is riding an elevator. The elevator has bristles running up the side of the tracks so her jeans are rubbing against them. When he gets to the top of the elevator she accidentally brushes a piece of metal and gets a small electric shock from it. Will objects moving from one object to anothr cause the first to become positively charged or negatively charged?

A:
positively