相同质量的下列物质，完全燃烧后生成CO2最多的是
A．CH4
B．C2H2
C．C2H4
D．C2H6
答案：B
Although human evolution has _______ in the past 10,000 years, we are changing our environment faster still.
A．linked up
B．loaded up
C．sped up
D．split up
PKPM算桩承台能不能考虑剪力墙的刚度？
