Answer:
A crystal face tends to be dull and rugged where a cleavage plane (most commonly seen in mica) is smooth and shiny, only being dull towards the edges it splits.
Answer: Usually on a map, solid lines represent boundaries between nations, or if it is a map of the states, it would represent the borders of the states.
Explanation:
Convection is a process which transfers the heat between the temperatures when fluid (i.e. liquid or gas) is in motion. Due to the presence of heat source, water temperature increases and also it will become less dense and rise. Hot air is less dense than cold. When air rises higher in the atmosphere its pressure gets down and it becomes colder.
