问题
选择题
设等差数列{an}的前n项和为Sn，则a6+a7>0是S9≥S3的[ ]
A．充分但不必要条件
B．必要但不充分条件
C．充要条件
D．既不充分也不必要条件
答案
答案：A
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设等差数列{an}的前n项和为Sn，则a6+a7>0是S9≥S3的[ ]
A．充分但不必要条件
B．必要但不充分条件
C．充要条件
D．既不充分也不必要条件
答案：A
My First Job Jay Leno is a very famous TV host in NBC．He started his talk show titled The Jay Lena Show in September 2009．It was a very popular TV programm in America．Here is the story of his first job． I gained a very strong work concept from my parents, both of whom lived through a hard period of time-the Great Depression （大萧条）．They couldn't ___36___ people who didn't work regularly．I once told my mom that Sylvester Stallone was getting $12 million for ten weeks of work．"What's he going to do the rest of the _37__?" she asked． I took my first job at Wilmington Ford near my homerown of Andover, Massachusetts, when I was 16．I worked until five or six o'clock on school days and __38____ 12-hour days during the summer as a prepper（擦洗汽车的小工）．This meant washing and polishing the new cars, and making sure the paper floor mats were in __39__．Another responsibility was taking off the hubcaps (车轮毂盖） at night, so they wouldn't get stolen, and 40 them the next day．This was 41 work because we had about seven acres of 42 One day, carrying an armful of hubcaps 43 a corner, I almost __44__ our new general manager．Scared, I dropped them all．He __45 me on the spot． I was too ashamed to tell my parents．Every day for about two weeks, I stayed __46 until evening．Then I would go home and say I had a ．__47___ day at work． Trying to make a last 48 , I wrote a letter to Henry Ford II and told him what happened．I said that we were a reliable Ford family and that when I was old enough, I was going to buy a Mustang． __49__ the owner of the dealership(经营店） called．"I don't know who you know in Detroit．" he said．"but if you want your job back, you've 50 it.” Later, during college, I wanted to work at a Roils-Royce dealership, but the owner said there were no openings．So 1 started washing cars there anyway．When the ___51__ noticed me, I said I was working until he _52__ me．He did．And the second day, I started to work there as a sales clerk． It 53 persistence (坚持） to succeed．Attitude 54_ matters．I have never thought I was better than anyone else, but I have always believed I couldn't be _ 55 ．
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