一竖直弹簧下端固定于水平地面上，小球从弹簧的正上方高为h的地方自由落下到弹簧上端，如图5-5-4所示，经几次反弹以后小球落在弹簧上静止于某一
Hi! My name is Jenny. I am a student in PEP Middle School in Hangzhou. And I have a friend, Bob at school. Do you want to know my family? Here is a photo of my family. These are my grandparents. They
“Are there any post offices ________ around here?” asked the man. A adaptable B comfortable C convenient D available
The news got around the world; people came from___________to see the wonder. A．somewhere B．everywhere C．anywhere D．nowhere
目前，北京文化创意产业发展迅速，创造的产值达960多亿元，占北京市GDP的14%以上，文化创意产业已成为北京服务业的重要组成部分。发展文化创意产
集合A＝[0,2π]，B＝{α|sin α<cos α}，则A∩B＝________________.
下列各项说法有误的一项是（ ）（3分） A．“青年最富有朝气、富有梦想，青年兴则国家兴，青年强则国家强。”这句话中的标点符号
，则
的取值范围是 . 
解析: