皮皮学,免费搜题
登录
搜题
【单选题】
LD 的发光出光性质为
A.
非相干光 自发辐射
B.
相干光 受激辐射
C.
非相干光 受激辐射
D.
相干光 自发辐射
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
【判断题】描述晶体的双折射现象,说明正负单轴晶体的特性。
A.
正确
B.
错误
【单选题】— ______ have you learned to play the piano? — For five years. [     ]
A.
How far
B.
How often
C.
How long
D.
How soon
【单选题】_______ is the distance from the mount to the river? [     ]
A.
How far
B.
how soon
C.
how often
D.
how long
【单选题】-________have you visited the Great Wall? -Once. [     ]
A.
How many times
B.
How often
C.
How soon
D.
How long
【单选题】下列微生物中不能利用分子氮的是
A.
霉菌
B.
弗兰克氏菌
C.
根瘤菌
D.
圆褐固氮菌
【单选题】---How amazing the noodle is! ---Yes, it is ________, and breaks the Guinness World Record as the longest handmade noodle.
A.
1704-meter-long
B.
1704-meters-long
C.
1704 meter long
D.
1704 meters long
【单选题】某企业飞先后斥巨资于发电厂、控股制药厂,收购百货公司,这种多元化增长属于( )
A.
集团多元化
B.
垂直多元化
C.
水平多元化
D.
同心多元化
【简答题】阅读下列程序: #include int main( ) { float x; x=1.0/2+1.0/4; printf(“\nx=%f\n”,x); return 0; } (1) 程序的运行结果是: 。 (2) 如果代码中相应的表达式改为 x=1/2+1/4 ,则运行结果是 。
【单选题】The scientists are not sure__________ 查看材料
A.
how long the ice age lasted
B.
where ice sheets melted during the ice age
C.
what caused the temperature changes
D.
what the earth is made up of
【单选题】—______ have you studied English? —Not long, just for a month. [     ]
A.
How soon
B.
How many
C.
How long
D.
How
相关题目: