On the island, at points marked with numbers 1, 2 and 3 in the figure, atmospheric pressure was simultaneously measured. Arrange these points in order of increasing atmospheric pressure, starting with the point where the atmospheric pressure was the lowest. Write the resulting sequence of numbers in the answer.

Explanation:

The image shows a cross-section of an island with points 1, 2, and 3 at different altitudes. Point 1 is at sea level, point 2 is at a moderate elevation, and point 3 is at the highest elevation. Atmospheric pressure decreases with increasing altitude. Therefore, the point with the lowest atmospheric pressure will be at the highest altitude, and the point with the highest atmospheric pressure will be at the lowest altitude.

Arranging the points in order of increasing atmospheric pressure (meaning from lowest pressure to highest pressure, which corresponds to highest altitude to lowest altitude):

1. Point 3 (highest altitude) - lowest pressure
2. Point 2 (middle altitude) - intermediate pressure
3. Point 1 (sea level, lowest altitude) - highest pressure

Answer: 321