（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．

如果2(x+3)的值与3(1-x)的值互为相反数，那么x等于(   )

阅读理解

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        A scientist working at her lab bench and a six-old baby playing with his food might seem to have little in common.After all,the scientist is engaged in serious research to uncover the very nature of the physical world,and the baby is,well, just playing…right? Perhaps,but some developmental psychologistshave argued that this“play”is  more like a scientific investigation than one might think.

        Take a closerlookat the baby playing at the table.Each time the bowl of rice is pushed over the table edge,it falls in the ground---and, in the process, it belongs out important evidence about how physical objects interact ; bowls of rice do not flood in mid-sit, but require support to remain stable. It is likely that babies are not born knowing the basic fact of the universe; nor are they ever clearly taught it. Instead, babies may form an understanding of object support through repeated experiments and then build on this knowledge to learn even more about how objects interact. Though their ranges and tools differ, the baby’s investigation and the scientist’s experiment appear to share the same aim(to learn about the natural world ), overall approach (gathering direct evidence from the world), and logic (are my observations what I expected?).

        Some psychologists suggest that young children learn about more than just the physical world in this way---that they investigate human psychology and the rules of language  using similar means. For example, it may only be through repeated experiments, evidence gathering, and finally overturning a theory, that a baby will come to accept the idea that other people can have different views and desires from what he or she has. for example, unlike the child , Mommy actually doesn't like Dove chocolate.

     Viewingchildhood development as a scientific investigation throws on how children learn ,but it also offers an inspiring look at science and scientists. Why do young children and scientists seem to be so much alike? Psychologists have suggested that science as an effort ---the desire to explore, explain, and understand our world---is simply something that comes from our babyhood. Perhaps evolution provided human babies with curiosity and a natural drive to explain their worlds, and adult scientists simply make use of the same drive that served them as children. The same cognitive systems that make young children feel good about feel good about figuring something out may have been adopted by adult scientists. As some psychologists put it, ”It is not that children are little scientists but that scientists are big children.”