1 The largest school district by enrollment with an election in 2016 is Wake County Public School System with 153,534 K-12 students.  The smallest North Carolina school district among the nation's largest with an election in 2016 is Duplin County Schools with 9,628 K-12 students.
Freon only remains a liquid while under pressure inside your refrigerator's cooling system. The chemical changes to a gas as soon as it contacts the air. This means, when you smell freon in and around your refrigerator, you're also inhaling varying amounts of freon gas. According to the Environmental Protection Agency, freon gas is denser than air and travels very slowly to the upper atmosphere.
Hydrogen has a RMM of 2; nitrogen has a RMM of 28 and oxygen has a RMM of 32. Air is a mix of nitrogen and oxygen, so will have an average RMM of about 29. That is 14.5 times as much as hydrogen, so air is 14.5 times as dense as hydrogen. And it's simple to do the same for other gases. Carbon dioxide has a RMM of 44 (12+16+16), so it is 44/29 = 1.5 times as dense as air.