1. What does the professor mainly discuss?
A. A weather phenomenon associated with continental polar air masses
B. A recent study comparing snowfall statistics in different regions
C. Ways in which air masses interact to create different types of precipitation
D. The formation of continental polar air masses in northern and Arctic regions
2. According to the professor, what is true of a continental polar air mass when it forms? Click on 2 answers.
A. Its temperature is fairly consistent
B. It has low levels of humidity.
C. It is somewhat turbulent.
D. It moves north toward cold regions.
3. Lake Superior is the northernmost Great Lake Compared with the other Great Lakes, what can be inferred about Lake Superior based on its location?
A. It does not produce as many clouds that can rise into a polar air mass.
B. The cities on its downwind shores receive more snow compared to cities near other lakes.
C. There is a greater difference between its temperature and that of the land surrounding it.
D. The lake-effect snowstorms that it produces tend to be less intense than storms near other lakes
4. The professor describes the process by which someone in the Middle Ages became a master of a trade
Put the steps in the correct order. Click on a phrase Then drag it to the space where it belongs
4. Heavy snowstorms occur when the polar air mass hits land.
A. The polar air mass becomes unstable
B. The lakes absorb large amounts of energy from the Sun and air.
C. The polar air mass acquires heat and moisture from the lakes
5. Why is Thunder Bay not very affected by lake-effect snow?
A. It is located close to a lake that protects it.
B. It is located on the northwestern shore of a lake.
C. It is located in a region that is too warm to receive much snow
D. It is located near a lake that is too small to produce much snow
6.What is the professor’s opinion about the future of lake-effect snowfalls?
A. They will vary greatly from year to year.
B. They will definitely become more frequent.
C. They will begin occurring earlier in the year.
D. It is possible they will occur less often than they do now
答案：A AB C BCA B D