The average adult aged 19-50 should consume 1000mg per day of calcium.
a. true
b. false

That statement is true
Calcium is very important in maintaining healthy bone density, strong teeth, and improve muscle contractions.
As we got older, our bones capability to regenerate is decreasing which make it harder for older people's bone to be healed when it's broken., so it is really important to start consuming a required amount of calcium since the early age.

The answer is d. when it begins to fall back to the child's hand

The short-term effect of tar on the body is increased blood pressure.