2. Make a natural layer of a green house gases surrounds the earth. It keeps the earth warm. From the book in the library, learn about the gases that forms this layer. What would have happened if the layer was not there? You can take help of various books or internet.

because natural gas is colorless, odorless, and tasteless, distributors add mercaptan (a chemical that smells like sulfur) to give natural gas a distinct unpleasant odor (it smells like rotten eggs). they locate the types of rock that are likely to contain natural gas deposits.

answer seismograph;