某蛋糕店每天制作生日蛋糕若干个，每个生日蛋糕的成本为50元，然后以每个100元的价格出售，如果当天卖不完，剩下的蛋糕作垃圾处理．现需决策此蛋糕店每天应该制作几个生日蛋糕，为此搜集并整理了100天生日蛋糕的日需求量（单位：个），得到如图3所示的柱状图，以100天记录的各需求量的频率作为每天各需求量发生的概率．若蛋糕店一天制作17个生日蛋糕．

根据短文内容判断下列句子正误。
    My name is Amy. Tomorrow is Saturday. My parents aren't going to work, but we are going to be very busy tomorrow. My mother is going to buy something. I'm going to the bookstore in the morning. Then I'm going to buy a dictionary.
    Tomorrow evening we are going to visit my grandparents and have a big dinner. After that we are going to the cinema. I think we are going to have a nice weekend.

下列有关对人体消化系统的描述中，不正确的是 （    ）

下列实验现象描述不正确的是（   ）

吉林省和黑龙江省山水相连,共同穿过两省的山脉和河流是(    )