题目

 Nanjing and Hangzhou summer camps offered     We are looking for hard-working and open-minded English teachers to join the Nanjing ( Jiangsu Province) and Hangzhou ( Zhejiang Province) summer camps !     Both of the summer camps will run from the beginning of July to the end of August. You will be expected to teach spoken English to Chinese students of different ages. We encourage you to bring your own culture to the classes to make things more interesting.  The information of the Nanjing camp:     ● Working hours: 40 hours per week, 5 working days per week.     ● Sa有一种盐，名称是“硝酸钡”，它的化学式是（　　）A．BaNO3B．BaSO4C．Ba（NO3）2D．Be（NO3）2