Explain valley?
What is gravel?
What is coal?
How can we calculate or estimate the evaporation from lakes?
What is the mantle made of?
What is natural resource?
Explain how continental heat flow is produced?
What is magnetism?
How do you calculate the age of earth?
What is crusher?
What is the general statement regarding the temperature of water in oceanic depths?
What is the earth made of?
Name the three major types of rocks?
Explain the examples of techno fossils?
Explain the difference between a semi-precious and a precious stone?