题目

There ____________ a bank  and  two pay phones near here.               A. has                  B. have                  C. are                    D. is 答案：D某种有机化合物R完全燃烧的化学方程式如下：2R+3O2 点燃 .  4H2O+2CO2，根据质量守恒定律，R的化学是（　　）A．CH3OHB．C2H5OHC．C2H4D．CCl4