已知平面向量$\overrightarrow{OA}$与$\overrightarrow{OB}$的夹角θ∈60°，120°，且|$\overrightarrow{OA}$|=|$\overrightarrow{OB}$|=3，若$\overrightarrow{OP}$=$\frac{1}{3}$$\overrightarrow{OA}$+$\frac{2}{3}$$\overrightarrow{OB}$，则|$\overrightarrow{OP}$|的取值范围是____ 

   Everybody knows vegetables and fruit are g____for people．Many people eat some fruit each day．Mr and Mrs Smith like e____ fruit very much and every day Mrs Smith goes to buy some fruit in the shop near her home. She can buy all k____ of fruits there，such as apples，pears, oranges and bananas．In different time of the year the p____ of each kind of fruit is not the same，s____  high，sometimes low. Mrs Smith usually t____  to buy cheap fruit．And b____  are Mr Smith’s favourite fruit．Mrs Smith buys bananas for him every week．But she always chooses the cheap ones.“Eating fruit can help to keep f____ ，" said Mr Smith．“It's quite d ____ from snacks．Both of them can give us energy．But snacks l____ cakes, chocolates and sweets are not good for our health at all," 

实验室模拟合成氨和氨催化氧化的流程如下：

已知实验室可用饱和亚硝酸钠（NaNO₂）溶液与饱和氯化铵溶液经加热后反应制取氮气．

（1）从图中选择制取氮气的合适装置：____ （填编号）

（2）氮气和氢气通过甲装置，甲装置的作用：①____ ②____ ③____ 

（3）用乙装置吸收一段时间氨后，再通入空气，同时将经加热的铂丝插入乙装置的锥形瓶内，能说明反应发生的现象是____ ，乙装置中的CCl₄的作用是____ ．

（4）反应结束后锥形瓶内的溶液中含有的离子有：H⁺、OH^﹣、____ 、____ ．