In 1973, I was teaching elementary school. Each day,27kids1“The Thinking Laboratory.” That was the 2 students voted for after deciding that “Room 104” was too3.

    Freddy was an average4,but not an average person .He had the rare balance of fun and compassion（同情）.He would5 the loudest over fun and be the saddest over anyone's6.

    Before the school year7,I gave the kids a special 8, T-shirts with the words “Verbs Are Your9” on them. I had advised the kids that while verbs（动词）may seem dull ,most of the10 things they do throughout their lives will be verbs.

    Through the years, I'd run into former students who would provide 11 on old classmates. I learned that Freddy did several jobs after his 12 from high school and remained the same 13 person I met forty years before .Once, while working overnight at a store, he let a homeless man 14in his truck. Another time ,he 15a friend money to buy a house .

    Just last year, I was16 a workshop when someone knocked at the classroom door. A woman17 the interruption and handed me an envelope. I stopped teaching and 18 it up. Inside were the “Verbs” shirt and a 19 from Freddy's mother. “Freddy passed away on Thanksgiving. He wanted you to have this.”

    I told the story  to the class. As sad as it was, I couldn't help smiling. Although Freddy was taken from us, we all20something from Freddy.

⑴为使实验误差更小，林红不宜采用图____（选填“甲”或“乙”）装置方式来估测大气压强．

⑵林红采用正确的装置方式进行测量，实验步骤如下：

①．把注射器的活塞推至注射器筒的底端，然后用橡皮帽封住注射器的小孔；

②．用细尼龙绳拴住注射器活塞的颈部，绳的另一端与弹簧测力计的挂钩相连，沿正确的方向慢慢拉动注射器筒，当注射器的活塞开始滑动时记下弹簧测力计的示数F；

③．读出注射器的容积V；

④．用刻度尺测出注射器的长度L．

⑶实验分析与数据处理：

a．实验步骤①的目的是____；

b．指出实验中的错误步骤：____（填数字序号），并进行纠正：____；

c．用测得的物理量表示大气压强的表达式p=____．

⑷实验时，可先在活塞周围涂抹润滑油，然后将其插入针筒中，这样做有两个好处；一是减小____；二是活塞的密封性好．

⑸实验室有A、B两个注射器，活塞的横截面积分别为0.5cm²和2cm²，若弹簧测力计量程为10N，实验时应选用A注射器，不选用B注射器的理由是____．

No one knows how the huge rocks _______ and _______ without our modern machines eight hundred years ago.

已知数列{a_n}的前n项和为S_n，且满足a_n=2S_n+1（n∈N*）．

（Ⅰ）求数列{a_n}的通项公式；

（Ⅱ）若b_n=（2n﹣1）•a_n，求数列{b_n}的前n项和T_n．