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.
Every four years the president, vice president, one-third of the Senate, and the entire House are up for election (on-year elections). On even-numbered years when there isn't a presidential election, one-third of the Senate and the whole House are included in the election (off-year elections).