现有KCl和KBr的混合物3.87 g,将混合物全部溶于水,并加入过量的AgNO3溶液,充分反应后产生6.63 g沉淀物,则原混合物中钾元素的质量分数为
What I need is_____ book that contains ______ABC of oil painting.
Jenny nearly missed the flight______ doing too much shopping.
The CDs are on sale! Buy one and you get ______ completely free.
I’m sure that your letter will get______ attention. They know you’re waiting for the reply.
All the dishes in this menu, ______ otherwise stated, will serve two to three people.