根据材料内容，选择正确答案。
There are 50 students in Class 8. Now they are doing a survey about how they spend their pocket money. Some spend it on books, and others spend it on visiting. What about you? Please read the form and answer the questions.
10%
55%
12%
13%
Buy some CDs and computer games.
Buy some snacks and drinks.
Buy some books in the bookshop.
Save it up and spend it traveling on holiday.
Buy some gifts for friends.
装置
物质
温度
现象
①
水+葡萄糖+酵母菌
25℃
有气泡产生，气球胀大
②
水+葡萄糖
没有气泡产生，气球不胀大
③
水+酵母菌
④
水十葡萄糖十酵母菌
0℃
