Passage VI

Earth's atmosphere consists of various gases and suspended liquid and solid matter. The atmosphere can be divided into layers based on air temperature and/or composition. Figure 1 shows the layers of the atmosphere, the altitude of the layer boundaries, in kilometers (km), and the air pressure, in millibars (mb), at those boundaries. Figure 2 shows the average air temperature, in degrees Celsius (°C), in arctic (cold) and tropical (warm) air masses at various altitudes. Table 1 shows air pressure and temperature readings from weather instruments carried into the stratosphere by balloons on 2 separate days.

31. According to Figure 2, at approximately which of the following altitudes would a weather instrument measuring air temperature be unable to distinguish between tropical and arctic air masses?

Answer and Explanation

Your Answer is

Correct Answer is B

Explanation

Look at figure 2. When the altitude of the ordinate is about 13.5 km and 22 km, the two curves intersect, and the temperature of the abscissa is equal. It is impossible to judge which curve the two points belong to according to the temperature