唐以前，市井成员主要是商贾、手工业者、小商小贩及部分无业游民。而到宋代，又出现了众多文化娱乐行业，饮食、旅店种类大增，众多文人也加入市井队伍中。材料中唐宋时期市井成员构成的变化（    ）

豌豆种子萌发过程中的吸水过程分为I、Ⅱ、Ⅲ三个阶段，三个阶段吸水的特点如右图所示。科学家研究发现，在第Ⅱ阶段种子O₂的吸收量大大低于CO₂的释放量，而在第Ⅲ阶段O₂的吸收就显著增加。下列有关种子萌发初期生理变化的说法错误的是（   ）

下面漫画反映的经济学道理是(   ) 
①商品的价值量由生产这种商品的社会必要劳动时间决定  ②价值决定价格   ③物以稀为贵    ④卖方市场

完形填空：阅读下面短文，从短文后各题所给的四个选项（A、B、C和D）中选出可以填入空白处的最佳选项。
    John entered a college and often worked late until 12 at night. He fell into the 1 of smoking a year ago. He smoked so much that he 2 had a cigarette on his lips. He 3 while he read, while he watched television and 4 while he drank a cup of coffee or tea. He smoked nearly forty cigarettes a day, but he was 5 about it.
    John's friend, Frank, 6 many times to 7 him not to smoke. “Smoking is bad for your 8!” he said, “You'd better give it up. ” But his advice didn't  9.
    Before long, John 10 that he often got a bad cough, 11 he went to see a doctor. The doctor 12 him carefully and asked whether he often smoked. John told him the 13. Then the doctor told him that his cough was 14 by smoking and he wouldn't get any better unless he stopped smoking.
“If not,” said the doctor, “you will never 15 from your cough and some other illnesses may also be caused.” John became 16 and made up his mind to give up smoking. At the beginning, it was very 17 for him. Every 18 when he wanted to smoke, he got something to eat. At last, he was not 19 smoking at all. And he no longer had 20.

往AgNO₃和Cu（NO₃）₂的混合溶液中加入一定量的锌粒,充分反应后过滤,往滤渣中加入稀盐酸,无气泡产生。你能得出的结论是（   ）