有机玻璃仪器的洗涤有哪些方法?
参考答案:
一般方法是用水、洗衣粉、去污粉刷洗,另外还可以用洗液洗涤,常用洗液有:铬酸洗液,盐酸,碱液和合成洗涤剂,有机溶剂洗涤液等。
Though having lived abroad for years, many Chinese still ______ the traditional customs. [ ]
A. perform
B. possess
C. observe
D. support
7÷11的商用循环小数表示是______,把商保留两位小数是______,保留三位小数是______.