Law of Constant Proportion

If $0.2 \mathrm{mol}$ of the calcium carbonate is required, how many grams of calcium carbonate should be taken?

If $0.2 \mathrm{mol}$ of the magnesium oxide is required, how many grams of magnesium oxide should be taken?

If $0.2 \mathrm{mol}$ of the sodium chloride is required, then how many grams of sodium chloride should be taken?