第20题: [单项选择]下列叙述中正确的是( )。 A. 软件交付使用后还需要进行维护 B. 软件一旦交付使用就不需要再进行维护 C. 软件交付使用后其生命周期就结束 D. 软件维护是指修复程序中被破坏的指令 参考答案:A 答案解析:[解析] 软件生命周期一般可以分为软件定义、软件开发及软件运行维护3个阶段。软件交付并投入运行后,需要不断地进行维护,并根据新提出的需求进行必要而且可能的扩展和删改。
第21题: [单项选择]地球内部圈层划分的依据是() A. 温度的垂直变化 B. 地震波速度的变化 C. 内部压力的变化 D. 物质密度的变化 参考答案:B 答案解析:
第30题: [单项选择]{{B}}Question 11 to 18 are based on the conversation you have just heard.{{/B}} A. She needs to get more rest. B. She took a rest last week and it helped her a lot. C. She wasn’t interested in last week’s lecture. D. She was surprised to find the lecture so easy. 参考答案:B 答案解析:[听力原文]
M: Sorry, you missed the discussion on Man and Nature. I heard that you were not feeling wel