题目

阅读下面短文，把A—D四个句子填入文中空缺处，然后完成第5小题。 3Dprinters have been around us for some time. There is a lot you can do and image with a 3D printer. ____ 1   A company in China has recently used 3D printers to make ten full-sized housed in just 24 hours. __ 2_. These houses are printed with special “ink ”that has been made from industrial construction waste. The using of cheap materials makes it possible to print each house under ＄500 The CEO of the company says , “___ 3____ ”He plans to set up 100 recycling factories across China an列式计算．（1）一个数是6的6倍，这个数是4的几倍？（2）6乘325与52的差，积是多少？（3）在一个减法算式中，减数是273，差是327，被减数是？