已知{an}为等差数列，且a3=﹣6，a6=0． （Ⅰ）求{an}的通项公式； （Ⅱ）若等比数列{bn}满足b1=﹣8，b2=a1+a2+a3，求数列{bn}的前n项和公式．
设NA表示阿伏加德罗常数的值，下列说法中正确的是 A、1 mol NH4+ 所含质子数为10NA B、10克氖气所含原子数约为NA C、22.4 L SO
Robert Frost was one of America’s best known and most honored serious writers. But his fame came late in his life. He was born in San Francisco, California in 1874. He lived in California during h
“共争青岛归来，同看国贼罢黜；欢呼学生复课，庆贺商店开门。”以上这幅对联反映的历史事件是 A、保路运动 B、五四运动 C、五卅运动
Sometimes people come into your life and you know at once that they were sure to be there.They serve some sort of purpose(目的)，teach you a lesson or help find out who you are or who you want t
中华文明以农耕文化为基础。最能体现半坡原始农耕文化成就的是 A、粟的种植 B、水稻的种植 C、陶器的炼制
下列的“望”意义完全相同的是 ①吾尝跂而望矣，不如登高之博见也②并汾乔木，望秋先陨③以我应他人，君还何所望④缦立远视，而望幸焉⑤
图1是两种高等生物细胞亚显微结构模式图。图2—4是图1中部分结构的放大，据图回答。（[ ]内填图中标号， 上填适当内容的文字。） （
