Is it convenient to talk at the moment? http://accesstocompletion.com/how-much-does-generic-singulair-cost.pdf singulair 5 mg prospect Exchanges began as member-owned trading platforms, but havetransformed over the years into for-profit businesses. At thesame time, regulatory changes put in place by the SEC, alongwith advances in technology and the automation of the markets,have blurred the distinctions between exchanges and tradingplatforms owned by broker-dealers, SIFMA said.