在同一试验中，其他条件不变的情况下，关于样本含量的估计下列哪种说法是正确的（） A.
题型：单项选择题
问题：
在同一试验中，其他条件不变的情况下，关于样本含量的估计下列哪种说法是正确的（）
A.α越大，N越大
B.β越大，N越大
C.σ越小，N越大
D.δ越大，N越大
E.检验效能越大，N越大
题型：单项选择题
阅读理解
If you are above the age of 40 then there are chances you would not know much about Snap Music.
But if that is the case, then ask your daughter or son, and perhaps, they'd even perform it for you. Indeed, Snap Music is one of the cool hip hop rap styles that support hip hop music. In simple words, Snap
Music is the music to which you "snap (捻着手指发劈啪声) your fingers and move with the rhythm.
This may seem relatively easy, but sure enough, it has its share of uniqueness which makes it stand apart.
The theoretical and technical characteristics of Snap Music are slow-paced beats, regular and timed
snapping of fingers, which created pleasing rhythms. Often as rappers rap, they get the audience clapping
or snapping along with them.
Snap Music was from Atlanta. It gradually made its way to the other parts of America. It is generally
believed that Snap was inspired by Crunk Music and it is Atlanta's Crunk style. But they are quite
different. While Crunk has high energy, Snap has an unhurried feel to it . An occasional whistle
or a
polyrhythmic (多节奏的) combination can he heard; this is done to improve the feeling of the music. It is
also said that the music was made for the club-crowd and at first was meant for dance lovers; but as the
form developed, it turned out to be rather slow.
There is a wide audience for this type of music. Here , this type of hip hop music is often simple with
not much depth or story. But then again, how many rap songs have depths and story these days? So , if
you are a teenager or a young adult, you might just enjoy the change that Snap offers.
1. We can learn from the text that US Snap Music ________.
A. is well known for its fast beats
B. is most popular 
in Atlanta
C. is very similar to Crunk Music
D. has changed in the development process
2. Which of the following is NOT the characteristic of Snap Music?
A. simple stories
B. high energy
C. whistles
D. diverse rhythms
3. The text is written to ____________.
A. advise people to enjoy Snap Music
B. explain why people like Snap Music
C. teach teenagers to perform Snap Music
D. give a brief introduction to Snap Music
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