继承机制的作用是
A.信息隐藏
B.数据封装
C.定义新类
D.数据抽象
参考答案:C
解析: 数据封装就是数据抽象,即信息隐藏;而继承是实现程序复用的基础。
Pierre Curie stopped his research and _____ Marie in the search of an unknown material.
[ ]
A. attended
B. joined
C. took part in
D. joined in
19世纪中期美国有哪几家著名的廉价报纸简述它们的共同特点。