a. Do bones stop growing?
b. How much water does contain the brain?
c. Do you have hair on your tongue?
d. How many square metres an adult's skin covers?
e. Does hair grow faster in hot weather?
f. How long does it take the heart to pump blood around the body?
g. Do muscles pull or push?
h. Which vitamin does the liver produce?
i. How many times a day do you breathe in and out?