计算机软件系统是指（）和程序运行时所需的数据及有关文档资料。
A、硬件
B、运算器
C、软件
D、内存
参考答案：C
The reason _____ he was late for the meeting was ____ his little son fell ill this morning.
A．for,that
B．why,that
C．for,because
D．why,because
磁罗经系数只与（）因素有关。
A.航向
B.船位
C.航速
