You should be able to talk during moderate exercise, but won't be able to sing, because it would disrupt breathing.
The human body cannot go without water for up to a week, so this is false
1. eating healthy foods.
2. getting enough sleep.
3. getting enough exercise
4. managing stress
5. washing your hands consistently.
All of those things helps your immune system by strengthening it or by keeping germs away which intern helps prevent you from getting sick.
I hope this helps. Let know if anything is unclear.
Begin to store calories in the form of fat. This increase body mass and you become over weight. If you continue to gain more calories each day you can become obese. This condition leads to health problems such as high blood pressure and diabetes.