根据短文理解选择正确答案。

      A good way to pass an exam is to work hard every day in a year. You may fail （不及格）in the exam if you are lazy for most of the year and then work hard only a few days before the exam. If you are taking an English exam, do not only learn rules of grammar. Try to read stories in English. Speak in English whenever（无论何时）you can. A few days before the exam you should go to bed early. Do not stay up late at night studying. Before you start the exam, read carefully over the question paper（试卷）, try to understand the exact(确切的) meaning of each question. When you have finished your exam, read over your answers. Correct(改正) the mistakes if there are any, and be sure that you have not missed anything out.

找出质数和合数(按题中数的顺序填写)

23，35，47，24，51，63，72，91，111

某口袋中有红色、黄色、蓝色玻璃球共72个，小明通过多次摸球试验后，发现摸到红球、黄球、蓝球的频率为35%、25%和40%，估计口袋中黄色玻璃球有 ____个．

按课文《有趣的汉字》填空。

“日”和“月”合在一起就是 “____”。上边“小”，下边“大”，就是“____”。我们祖先创造的汉字多么有趣啊！