题目

TYPING This course is for those who want to learn to type, as well as those who want to improve their typing. The course is not common. You are tested in the first class and begin practicing at one of eight different skill levels. This allows you to learn at your own speed. Each program lasts 20 hours. Bring your own paper. Course fee: $ 125   Materials: $25 Two hours each evening for two weeks. New classes begin every two weeks. This course is taught by a number of qualified business education teachers who have successfully taught typing courses before. UNDERSTANDING COMPUTERS This twelve-h若不等式组有解，则a的取值范围是（  ）A.a＞－1.    B.a≥－1.    C a≤1.    D.a＜1.