If you know the mass and volume of an object, how can you predict whether it will float or sink in water ?

Try to answer all questions if possible i will take anything this is worth 21 ! ! 1. what rights do citizen's have in a monarchy? 2. what countries practice monarchy? 3. what is one advantage of a monarchy? 4. what is one disadvantage of a monarchy? 5. what rights do citizen's have in a dictatorship? 6. what countries practice dictatorship? 7. what is one advantage of dictatorship? 8. what is one disadvantage of dictatorship?