A submarine fills a special storage area known as a ballast with water in order to increase its density. This allows it to dive deeper in the ocean. When a submarine needs to rise rapidly, compressed air is used to push the water out of the ballast. What effect does replacing the water in the ballast with air have on the submarine?

the submarine floats after replacing the water with the compressed air

The submarine will rise.

Explanation:

To get a submarine to surface, the main vents in the top of the tank are closed and high-pressure compressed air is blown into the ballast tanks, forcing the water out through the flood ports at the bottom of the tank. This increases the vessel's displacement.

the answer is 0.42 is that is an option. this question provides no info