a) It's caused by bacteria. Pericoronitis is an infection. It's caused by normal oral bacteria, like those found in dental plaque. It's the gum relationship around a partially-erupted tooth that allows pericoronitis to occur.
A futures exchange or futures market is a central financial exchange where people can trade standardized futures contracts; that is, a contract to buy specific quantities of a commodity or financial instrument at a specified price with delivery set at a specified time in the future. These types of contracts fall into the category of derivatives. The opposite of the futures market is the spots market, where trades will occur immediately (2 business days) after a transaction agreement has been made, rather than at a predetermined time in the future.
The CME is owned and operates under the CME Group. Chicago Board of Trade (CBOT): Established in 1848, the CBOT ranks as the oldest futures/options trading exchange in the world. The exchange offers more than 50 different futures and option contracts for investors stretching across a number of asset classes. As of 2007, the CBOT operates as a subsidiary of the CME group. New York Mercantile Exchange : The NYMEX is the worldâs largest physical commodity futures exchange, offering exposure to a wide variety of products.