A KEEPS B STANDS C MAINTAINS D REMAINSV. READ THE FOLLOWING TWO PA...

45. A keeps

B stands

C maintains

D remains

V. Read the following two passages and choose the correct answer for

each question.

Various types of fog are essentially clouds that form at the earth's surface, produced by

temperature differences and moisture in the air. As warm, moisture-laden air cools, its

relative humidity (the amount of moisture that air can contain, which depends on the

temperature) increases. Warm air can hold more water vapor than cold air. So if the air is

cooled

sufficiently

it will reach saturation, or the dew point, at which point the

moisture begins to condense out of the air and form water droplets, creating fog.