They are air, calcium chloride brine, sodium chloride brine, alcohol, and similar nonfreezing solutions. The purpose of Class 2 refrigerants is to receive a reduction of temperature from Class 1 refrigerants and convey this lower temperature to the area to be air-conditioned.
Elections for the United States Senate will be held on November 8, 2016, with 34 of the 100 seats in the Senate being contested in regular elections whose winners will serve six-year terms from January 3, 2017 until January 3, 2023.
Senators have 6-year terms. There are Senate elections every 2 years (the even years) where about 1/3 of the Senate is up for election. The Senators from the same state are never up for election at the same time. But during any 6 year period, both of your Senate seats will be up for election.