如图是某校六年级二班的期中考试成绩统计图，看图回答问题．本次期中考试数学学科的优秀率是____%．

《北史》载：“孝文帝引见朝臣，诏断诸北语，一从正音……于是诏：‘年三十以上，习性已久，容或不可卒革。三十以下，见在朝廷之人，语音不听仍旧。若有故为，当降爵黜官。’”下列对这一诏令的理解不确切的是(　　)

    I am John. I always get up late at the weekend. At about 9:30 am, I have breakfast. After breakfast, I start doing my homework. We have lunch at about 12:00, and then I watch TV or have a rest. I like reading and I often read some interesting books in the afternoon. I like sports, too. Sometimes I play football or basketball with my friends at school. My school is near my home, so I can walk there. Every weekend, my father takes me to a restaurant for a big dinner. I can enjoy lots of nice food. I like my weekend.