线性规划求解中，用最小比值原则确定换出变量，目的是保证解的可行性.该说法（）。
A.正确
B.错误
C.不一定
D.无法判断
参考答案：A
There were so many cars held up by the heavy rain on the road that we had no but to wait. [ ]
A. alternative
B. difference
C. relation
D. opposition
数据库存管理系统常见的灵敏据模型有层次、网状和 【8】 三种。
