皮皮学，免费搜题
登录
搜题
【单选题】
据报道，N 4 是一种形似白磷的分子， 18 O 2 是比黄金还贵重的物质。下列说法正确的是A.
18 O 2 与 16 O 2 性质完全相同
B.
N 4 ＝2N 2 是化学变化
C.
N 4 和N 2 互为同位素
D.
18 O 2 中含18个中子
拍照语音搜题，微信中搜索"皮皮学"使用
参考答案：
参考解析：
知识点：
皮皮学刷刷变学霸
举一反三
【简答题】创建性别表,可以将性别编号作为主码。CREATE TABLE 性别表 (No char(1) () KEY, Name nchar(4) NULL, )
【单选题】To be friendly and to be charming is not an art. The only need is to pay atrention to ourselves and to others.
A.
less, less
B.
less,more
C.
more, more
【简答题】翻译: 4.To be friendly and to be charming is not an art. The only need is to pay less attention to ourselves and more to others.
【判断题】创建性别表,可以将性别编号作为主码。CREATE TABLE 性别表 (SexNo char(1) PRIMARY KEY, SexName nchar(4) NULL, )
A.
正确
B.
错误
【判断题】To be friendly and to be charming is not an art. the only need is to pay more attention to ourselves and less to others.
A.
正确
B.
错误
【多选题】4To be friendly and to be charming is not an art. The only need is to pay____attention to ourselves and______to others.
A.
laugh
B.
enjoy your company
C.
less
D.
more
相关题目：