A because if you multiple it, you will be moving the decimal one time
Answer:
when silver articles exposed to air silver racts with Sulphur present in the atmosphere and form a black layer of silver sulphide on the surface. copper articles get tarnished by reacting with air and water. due to this, a layer is formed over copper vessels.
Because size of an atom INCREASES from top to bottom and DECREASES from left to right on the periodic table. If to elements are in the same period they can't increase in size based on the up or down trend. Instead, notice that Alkali Metals are LEFT of Alkaline Earth Metals. Therefore, the Alkali Metal will be larger than the Alkaline Earth Metals.