Answer:
1.sieving, I will use the sieving method this method is use to separate different sizes of substance by this method the sand will be separated from the sifter leaving the stone
2.Evaporation or boil it,Evaporation this method is use to separate liquid to solid if we use eveporation method the water will disappear leaving the salt
3.We can use hand picking method,since there are no instrument or method of separating may use we will use hand picking method this method will fit since we can identify the diffrent subtance
