Starting a new exercise regimen without consulting a doctor first can be dangerous, especially if you have previous injuries. true or false ?

Ihave a really high metabolism and only weigh 70 pounds (13 almost 14). people always ask me two questions: do you ever eat and how do you eat so much and stay so skinny.i am worried that a high metabolism wont me forever. what are some safe steps i can take to maintain being fit. (also, i already work out i am a dancer so i get cardio a lot)

In which book word demography is used for first time

When children are young and go to the doctor, the doctor will give them booster shots. this re-exposes the children to a dead portion of a disease to them build immunity.