1. In order for clouds to form, water vapor must rise, condense and latch on (hug or attach itself) to. A. the sun
B. dust
C. the ozone
D. None of the above

2. Tall masses of puffy, white clouds, with flat bases (bottom), that form when air currents rise are called clouds.

3. To keep track of high-and low-temperature areas, weather maps are drawn with lines connecting points of equal temperature. These lines are called .