（2014山东省实验中学高三第二次模拟考试）9．The publishers are confident that the books ______________ next month will sell well．

A．published

B．to be published

C．having published

D．are published

小刚在体育中考项目50m跑的测试中，体育老师记下了他跑到30m处所用的时间是5s．他跑这30m的平均速度是______m/s，合______km/h．