The picture below is a "vertical cross-section of the weather system on a certain day in April of a certain year", in which A (110°E, 40°N) and B (120°E, 30°N) are near-Earth

Small question 1:B

Small question 2:D

Test question analysis:

Small question 2:D p>

Quiz 1: Examine common weather systems. According to the principle of frontal cyclones, it can be seen that there is a warm front in the east and a cold front in the west, so C and D are excluded; according to the vertical profile of the weather system on a certain day in April of a certain year, the cold air mass in place A is controlled, and the warm air mass in place B is controlled, combined with the front schematic diagram , exclude A.

Small question 2: According to the above question, A is controlled by a cold air mass, the temperature is low, and the sandstorm is caused by the cold front, rule out A; B is a warm air mass in front of the front, with continuous precipitation, rule out B; According to the northern hemisphere cyclone The law of horizontal motion - counterclockwise convergence, so the wind is northerly in place A and the wind is southerly in place B, excluding C.