a) It is known that the area of Indian ocean is 25 million square miles.
Lets take the unknown ocean percentage as x, which is bigger than the Indian ocean.
So comparing to the size of that unknown x ocean, Indian ocean is just a small part (39%) of the area.
So,
Now, we have to compare the value of x with the data given in the table. It matches with the Pacific ocean.
Hence Indian ocean is a small part (39%) of Pacific ocean.
b) Given that the area of artic ocean is 5 million square miles. It is just a small percentage (16%) of some bigger ocean given in the table. Let's take the unknown ocean as y.