Fill in the blanks:
Fossil fuels are…………, ………….. and ………………….
Process of separation of different constituents from petroleum is called ……………..
Least polluting fuel for vehicle is …………………….
Fill in the blanks:
Fossil fuels are…………, ………….. and ………………….
Process of separation of different constituents from petroleum is called ……………..
Least polluting fuel for vehicle is …………………….