Answer to Question 1
Answer: Hail consists of multiple layers of ice that are usually no more than a few millimeters in thickness, but under extreme circumstances can achieve sizes comparable to softballs. Hailstones are often relatively concentric, though some have irregular shapes. No other type of precipitation is capable of producing drops or particles nearly as large as hail. Hail development begins with the formation of a small particle called an embryo, usually consisting of graupel, in a region of cloud where supercooled droplets coexist with ice crystals. The cumulonimbus clouds that produce hail do not have uniformly strong updrafts across their entire width; they have localized areas of extremely violent vertical motions surrounded by zones of relatively weak updrafts. Hail growth typically begins just outside these intense updrafts. Some developing hailstones get blown from the edge of the strong updrafts into the core, where they are rapidly taken to the upper reaches of the cloud and ejected. When this happens the stones do not have time to accumulate large amounts of ice, so they fall from the cloud as relatively small hail. Sleet forms when raindrops freeze in the air while falling.
Answer to Question 2
Answer: microwave
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