2. Midlatitude cyclones in the Northern Hemisphere ___________.

a. have cold fronts but not warm fronts
b. travel from east to west
c. are large high-pressure systems
d. rotate counterclockwise
e. are associated with clear skies
answer: d

16. Sheet lightning __________.
a. accounts for about 20 percent of all lightning
b. occurs within clouds
c. is the most dangerous type of lightning
d. is seen as a distinct stroke
e. All of the above are true
answer: b

18. In which month are tornadoes most likely to occur in the United States?
a. August
b. October
c. July
d. May
e. March
answer: d

correct.

2. Midlatitude cyclones in the Northern Hemisphere rotate counterclockwise.

16. Sheet lightning occurs within clouds.

18. Tornadoes are most likely to occur in the United States in May.

To determine the answer to question 2, we need to understand the characteristics of midlatitude cyclones in the Northern Hemisphere. One key characteristic is their rotation. Midlatitude cyclones in the Northern Hemisphere rotate counterclockwise. Therefore, the correct answer is option d.

To determine the answer to question 16, we need to understand the characteristics of sheet lightning. Sheet lightning refers to lightning that occurs within clouds and is seen as a diffuse flash of light. It does not have a distinct stroke like other types of lightning. Therefore, the correct answer is option b.

To determine the answer to question 18, we need to know the month when tornadoes are most likely to occur in the United States. Tornadoes are most commonly observed in the United States during the spring season, particularly in May. Therefore, the correct answer is option d.