将植物横放,测量根和茎生长素浓度与其生长状况的关系如甲图所示,则曲线上P点最可能对应于乙图中的位置是()
A.a
B.b
C.c
D.d
参考答案:B
___ research ___ the universe scientists have put a lot of information ___ computers. [ ]
A. With; over; at
B. On; at; to
C. In; about; into
D. For; with; through
为防止异物吸入,影响设备正常安全运行,燃烧器风机入口应该装有()。