If an object's density is decreasing but its mass stays constant, what must be true of the object's volume?

Answer

The volume will be increased

Explanation

Look at the formula

If the mass increase the density will be increased because of their direct relationship. But in the case of constant mass. The volume increase the density will decrease because there is an inverse relationship exists between them. In the inverse relationship, the two objects perform differently. for example, if you are going to inflate the balloon, its volume will increase but density decrease

Neptune is the eighth planet from the sun. it was the first planet to get its existence predicted by  mathematical calculations  before it was actually seen through a telescope on sept. 23, 1846. irregularities in the orbit of  uranus  led french astronomer alexis bouvard to suggest that the gravitational pull from another celestial body might be responsible. german astronomer johann galle then relied on subsequent calculations to   spot neptune via telescope. previously, astronomer galileo galilei sketched the planet, but he mistook it for a star due to its slow motion. in accordance with all the other planets seen in the sky, this new world was given a name from greek and roman mythology — neptune, the roman god of the sea.