Wall Street, global markets mostly lower and oil prices drop $2 on hopes for a US-Iran nuclear deal

By ELAINE KURTENBACH and MATT OTT, Associated Press Business Writers Wall Street veered lower before the opening bell Thursday and oil prices fell more than $2 a barrel as optimism over a possible U.S.-Iran nuclear deal rose. Futures for the S&P 500 and Dow Jones Industrial Average each fell 0.4%.…