2.3 Additional Questions :
Answer the following questions :
1. What is called the uppermost layer of the earth ?
Ans: The uppermost layer of the earth is called the crust .
2. Name the continents of the oceanic crust .
Ans: The continents of the oceanic crust are Silica and magnesium .
3. What is the radius of the core ?
Ans: The radius of the core is about 3500 km .
4. What are called igneous rocks ?
Ans: When the molten magma cools, it becomes solid. Rocks formed in this way are called igneous rocks .
5. Name the main mineral constituent of the continental areas .
Ans: The main mineral constituent of the continental areas are silica and alumina .
6. What are Fossils ?
Ans: The remains of the dead plants and animals trapped in the layers of rocks are called fossils .
7. What is earth crust in made of ?
Ans: The earth crust in made of rocks .