Western European nations maintained democratic political systems.
Hail .
There are many types of types of snow, sleet, hail, and freezing rain.
SORRY its not sleet
It was caused by a mix of different scenarios. Rome was constantly attacked by Barbarian tribes; they were over-expanded, which made it really hard for them to keep their entire empire under control; they had a lot of economic problems and relied too much on slave labor; and they spent way too much money on their military, just to name a few factors.
The answer is B. The Interoceanic Highway
I don't know what you mean by "D" climate regions, but the cooler the climate, the more likely permafrost will be found. If the climate is warmer, permafrost won't be found because it will be thawed out.
