设0<a<1，定义a₁＝1＋a，$a_{n+1}=\frac{1}{a_n}+a$ , 求证：对任意n∈N_＋，有$1<a_n<\frac{1}{1-a}$

一根条形磁铁自右向左穿过一个闭合线圈，则流过灵敏电流计的感应电流方向是（   ）

    There was a pet store and the owner had a parrot. One day a 1 walked in and the parrot said to the man ,“Hey you!” The man said, “What!?” The parrot said, “Your 2 is really ugly.” The man got very 3 and went to the store owner and said, “Your bird just  4 my wife. It said she was ugly.”

    The owner stormed over, 5 the bird, took it into the “black room,” shook it a bit, 6 out a few feathers, and said, “Don't ever, ever say anything to  7 my customers again. You got that！！！”

    With that 8 he took the bird and put it back into its cage. The old bird shook out its    9  and relaxed in its cage. A couple of weeks 10 and in walked this guy and his wife again. The parrot said, “Hey you!” The guy said, “What!?” The parrot answered, “You know that.”

如图是细胞膜局部放大模式图．请分析回答下列问题

（1）图中2代表____ 分子

（2）若该细胞表示人的白细胞，它所具有的吞噬功能与细胞膜的____ 有关．

（3）若该细胞表示人的小肠绒毛上皮细胞，它从肠腔中吸收葡萄糖的方式是____ ，需要图中的____ 协助运输（用图中的数字表示），运输方向是____ （用图中的字母及箭头表示）．