Answer:
The air molecules inside the bag are pushing out against the bag.
You should always have a medical exam to make sure it's safe to begin exercising. This can prevent potential damages to your body, or keep current problems from becoming worse. Regardless of whether or not you are exercising, you should have a check-up with your doctor at least once a year.
The author word choice of using words like ardour and avidity made it clear that the gentleman got very much pleasure reading based on the definitions of the two words. In fact, it's not a great stretch to say he had an addiction since it got in the way of his basic needs which is what the first sentence was basically shouting at the reader. My interpretation is that the man was to much in his thoughts to take care of himself. From that I concluded that him trying to understand the absolute meaning of Don Belianis broke his fragile state; the only thing that keep the gentleman going was his joyful understanding of complex books, but he couldn't understand a author of a great book's writing.
Answer:
By providing a way to study for tests