There is going to _____ a sports meeting in our school next week.

A．have

B．hold

C．be

D．do

血浆pH主要决定于下列哪种缓冲对（）

A.KHCO₃／H₂CO₃

B.NaHCO₃／H₂CO₃

C.K₂HPO₄／KH₂PO₄

D.Na₂HPO₄／NaH₂PO₄

E.Na₂CO₃／NaHCO₃