[This is the stem.]

Question

(2 points)
A , is when a warm air masses advances on a cold air mass and are expected to follow.

Answer 1

cold front

Answer 2

what is the second blank

Answer 3

thunderstorms

Answer 4

are those the correct answers

Answer 5

Yes, those are the correct answers. A cold front occurs when a warm air mass advances on a cold air mass, and thunderstorms are expected to follow.