A:until; which
B:when; that
C:before; that
D:as; which
北京和东京纬度相当,但夏季北京比东京热,冬季比东京冷,其主要原因是( )
反应时间(min)
0
5
15
17
20
X的浓度(mol/L)
1.0
0.4
0.7