Answer:
I think its never but sorry if im wrong
Magma. Magma can be made of many different materials, and once it breaches the earth surface it is called lava. Lava is what comes out of volcanoes, magma is what is still underground
Answer: B. It is useful for navigation.
Explanation:
The Mercator is a famous map projections that was created by Geradus Mercator who was a Flemish geographer in 1569.
The Mercator is used for nautical purposes and is regarded as the standard map projection due to the fact that the lines of true direction can be represented on it and hence useful for navigation.
