Air is an odorless (无气味的), invisible (看不见的) gas that surrounds the earth. It is everywhere

Air is an odorless (无气味的), invisible (看不见的) gas that surrounds the earth. It is everywhere on the planet. An “empty” drinking glass and an “empty” room, to give two examples, are not really empty. Each is filled with air. When the glass is filled with water, the water pushes the air out of the glass.
Air, as a gas, has no definite (明确的) shape, but, because it is matter, it takes up space. It is easy to prove that air is something that takes up space. Stuff a dry handkerchief into the bottom（底部） of a glass so that it will not fall out when the glass is turned upside-down. Push the upside-down glass; hold it straight into a jar of water till the glass is completely covered. When the glass is taken out of water, the handkerchief will be dry. The air inside the glass takes up space and keeps the water from coming in.
【小题1】What does the underlined word “Stuff” (in Paragraph 2) mean?A．Press tightly. B．Take out.C．Put down.D．Turn fully.【小题2】The writer tells us that .A．the experiment is done in the laboratoryB．the experiment is done outside the roomC．the experiment is easily doneD．the experiment is carried out indoors【小题3】Which of the following pictures gives us the correct result?
( W—water; A—air; H—handkerchief )
A

(答案→)A 解析：文章介绍了空气的特点，用实验证明空气是占据空间的。【小题1】猜词题：从后面的句子：so that it will not fall out when the glass is turned upside-down.杯子倒过来手帕不会掉，说明是紧紧的按压。选A【小题2】细节题：从第二段的句子：It is easy to prove that air is something that takes up space.可知这个实验很容易做。选C【小题3】细节题：从最后一段的句子：Push the upside-down glass; hold it straight into a jar of water till the glass is completely covered. When the glass is taken out of water, the handkerchief will be dry. The air inside the glass takes up space and keeps the water from coming in.可知杯子倒过来的时候，手帕在杯子底部，杯子的其余部分是空气。选C。

这个解释是对的