Question

The mass of first object 5.1*10^7gram and that of the second 9.6*10^6 gram which one is heavier?

Answer 1

According to your question, and my interpretation of the question,

You ask that there are two objects. one has mass of 5.1*10^7 gm and the other has mass of 9.6*10^6 gm. It is clear by looking at the question itself that the object which has mass 5.1*10^7 gm is heavier than the other object.