Do you mean; " A blank is a substance that is made by combining two elements?" (I'm not sure if substances is the right term)
If so then the blank is a compound.
Answer:
it burns things which would be burned easily by lightning, and then people put the fire out immediately. If the dried plants that they are lighting on fire are hit by lightning, it can lead to a massive fire without anyone realizing.
Last option that is none of above is right answer.
Negative is bad and positive is good
I believe it means that it takes a lot of heat in joules to make silicon vaporize so it stays solid until a great deal of heat has been added. By comparison, water has a latent heat of about 2260 joules per gram so vaporizes much more readily than silicon.