（Ⅰ）展开式中二项系数最大项；

（Ⅱ）若 ${\left(x+2\right)}^n=a_0+a_1\left(x+1\right)+a_2{\left(x+1\right)}^2$   $+\cdots +a_n{\left(x+1\right)}^n$ ，求① $a_1+a_2+\cdots +a_n$ 的值；② $a_1+2a_2+\cdots +n{a}_n$ 的值．

我国解决水资源季节变化大的最好办法是（　　）

阅读理解

    The winter holidays(假期)were here last ! It was Nami's job to make a gift for everyone in family．She did it every year.

    Grandma loves flowers．So Nami drew a picture of flowers for her grandma．Grandpa loves cakes．So Nami made her grandpa a strawberry cake．Cousin Miko loves elephants．So Nami wrote her cousin an elephant story．Uncle Yuri collects coins(收集硬币)．So Nami made her uncle a large clay(陶土)coin．

Nami didn't know what to make for Aunt Hoshi! She didn't know what was special to her aunt．Nami went to find it out．

    First，Nami saw that Aunt Hoshi had a photo of a baseball player in her room．Next．Nami saw Aunt Hoshi's socks．They had small pictures of baseballs on them．Then，Nami saw Aunt Hoshi watching baseball on TV Nami knew what to do．

    At last．it was time for Nami to give the gifts．Everyone was happy when they saw their gifts．Aunt Hoshi jumped(跳)up when she got her gift．

    "Let's play baseball !"she called．Then the family went out and played late into the night．

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