The Dow Jones Industrial Average dropped 1000 points minutes after the opening bell Monday thanks to fears about China’s economic slowdown. The index rebounded by 1 p.m. to being down about 150 points. Earlier in the day, the Shanghai Composite index dived 8.5 percent in what the state-run Xinhua New Agency called “China’s Black Monday.†Markets in Hong Kong, Japan, and Europe all tumbled; a combined $5 trillion was erased from global equity markets in the turmoil.