And although the U.S. auto industry has cut exhaust emissions substantially since the unregulated 1960s—hydrocarbons dropped by 99 percent, carbon monoxide by 96 percent and nitrogen oxides by 95 percent—the continued production of carbon dioxide causes c
And although the U.S. auto industry has cut exhaust emissions substantially since the unregulated 1960s—hydrocarbons dropped by 99 percent, carbon monoxide by 96 percent and nitrogen oxides by 95 percent—the continued production of carbon dioxide causes c
从毫无法规管制的1960年代至今，虽然美国汽车业界已经大幅减少排放的废气（碳氢化合物降低了99%，一氧化碳降低了96%，氮氧化物降低了95%），但持续产生的二氧化碳仍是个问题，因为它可能影响地球的气候。