Which correctly lists three characteristics that are used to describe air?

Rainbow trout is non- native to the united states. however this species is breeding with the native gula yltrout acientistrecently observed that the hola trout were becoming exitinct what is the cause of their extinction

As water is cooled from 4 c to 0 c its density

Can someone me? i need to have this done as soon as possible! i'm putting 20 points on this!