多选题：关于样式的描述，哪些是正确的（ ） A. 内部样式定义在网页文件的头部标签内 B. 外部样式定义在单独的样式文件中，用户需要在网页文件中引用该样式文件才能使用外部样式。 C. 内容样式必须写在 <style type="text/css"> 内部样式定义</style> 里面。 D. html内联样式定义在网页文件的头部。

A.呼吸性碱中毒
B.呼吸性酸中毒
C.代谢性酸中毒
D.代谢性碱中毒
E.无酸碱平衡失常

Books are steadily increasing in size: the average number of pages has grown by 25% over the last 15 years. A study of more than 2500 books appearing on New York Times bestseller reveals that the average length has increased from 320 pages in 1999 to 400 pages in 2014. According to James Finlayson, who carried out the survey, there ’s a “relatively consistent pattern of grow th year on year ”. For Finlayson, much of this shift can be explained by the industry ’s shift towards digital. He says “When you pick up a large book in a shop, you can sometimes be intimidated, but if you have a big book on a Kindle （eBook ）, that’s not a consideration. ”

A、时间短
B、速度快
C、飞得高
D、寿命长