问题
单项选择题
设计混凝土强度等级为C30，原材料分别为：胶凝材料：水泥为PC32.5，用量360kg/m3；水胶比为0.40。粉煤灰掺量占胶凝材料总量的20%。计算粉煤灰用量（）。
A.95
B.90
C.72
D.75
答案
参考答案：B
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设计混凝土强度等级为C30，原材料分别为：胶凝材料：水泥为PC32.5，用量360kg/m3；水胶比为0.40。粉煤灰掺量占胶凝材料总量的20%。计算粉煤灰用量（）。
A.95
B.90
C.72
D.75
参考答案：B
小题2:This kind of education may be in the form of self-study with proper guidance through the use of libraries, correspondence courses, or broadcasting. It may also be acquired collectively in schools and colleges, study groups, workshops, clubs, and professional associations. 小题3:Modern adult education for large numbers of people started in the 18th and 19th centuries with the rise of the Industrial Revolution. Great economic and social changes were taking place: people were moving from rural areas to cities; new types of work were being created in an expanding factory system. These and other factors produced a need for further education and re-education of adults. 小题4:The earliest programs of organized adult education arose in Great Britain in the 1790s, with the founding of an adult school in Nottingham and a mechanics’ institute in Glasgow. The earliest adult education institution in the United States was founded by Benjamin Franklin and some friends in Philadelphia in 1727. 小题5:People recognize that continued learning is necessary for most forms of employment today. For example, parts of the adult population in many countries find it necessary to take part in retraining programs at work or even to learn completely new jobs. Adult education programs are springing up constantly to meet these and other needs. |