I also believe the answer is A.
Answer:
Explanation:
some gases prevent the escape of heat from the earth.There will be an increase in the percentage of such gases would cause the average temperatures to increase world wide.This is known as greenhouse effect.Carbon dioxide is one of the green house gases.An increase in the carbon dioxide content in the atmosphere woul cause more heat to be retained by the atmosphere and lead to global warming.
Cells divide for many reasons. For example, when you skin your knee, cells divide to replace old, dead, or damaged cells. ... When organisms grow, it isn't because cells are getting larger. Organisms grow because cells are dividing to produce more and more cells.
Answer:
Common examples include carbon, sulfur, oxygen, iron, copper, aluminium. Elements are represented by symbols. Compounds are substances made from atoms of different elements joined by chemical bonds. They can only be separated by a chemical reaction.
Explanation:
Substances can be categorised as either elements or compounds. Both of these are made up of atoms, the only difference is an element is made of one type of atom whereas compounds are made of two or more different types of atoms.