—Ready to give up guessing, Sandy?

—No, no. Hold on! I think I _______ at the answer now.

A．arrive

B．have arrived

C．arrived

D．am arriving

水泥凝结时间的测定，需要将水泥加水调成（）的水泥浆。

A.0.5水灰比

B.0.30水灰比

C.标准稠度

D.流动