多项选择题
Which methods of organization you can use when you organize your main points? A. chronological order B. spatial order C. topical order D. problem-solution order
Which methods of organization you can use when you organize your main points? A. chronological order B. spatial order C. topical order D. problem-solution order
图，曲线为二次抛物线，横梁的抗弯刚度为2EI，竖柱的抗弯刚度为EI，则横梁中点K的竖向位移等于( )。
（向下）
（向下）
（向下）
（向下）