A:has been designed
B:had been designed
C:was designed
D:would be designed
以水为原料大量制取氢气,最理想的方法是 ( )
研究表明,每燃烧1吨生活垃圾可以发电200千瓦时,某垃圾发电厂有1台功率为6.0×103千瓦的发电机,若它每天工作10小时,则一天可以处理多少吨生活垃圾?