What do you understand by limiting reactant?
When in reaction, one rectant is in excess over the other. The reactant which is present in the lesser amount gets consumed after sometimes and after no further reaction takes place whatever be the amount of the other reactant present. Hence, the reactant which gets consumed, limits the amount of product formed and, therefore, called the liminting reagent.
What do you mean by significant figures?
Or
What do you know about significant figures? What are the rules for determing the number of significant figures?