赤道穿过哪些大洲的大陆部分（　　）

阅读下列短文，从每小题的三个选项中选出最佳答案

      It is morning now. Look at the sun, it rises in the east(东方). Look at the tree, the shadow is long. It is noon now. The sun is high in the sky. It is very hot. Look at the tree. The shadow is short. It is evening now. The sun goes down in the west(西方). Look at the tree, the shadow is long again. It is night now. The moon is high in the sky. There are some stars in the sky too.

用向量证明：若平面内的一条直线垂直于平面外的一条直线在该平面上的投影，则这两条直线垂直．

南京大学生小于起扶了摔倒在路边的老人，并将身上仅有的生活费赠给了这位患病老人。她的行为（）
①体现了中华民族的传统美德                      ②体现了强烈的社会责任感
③诠释了社会主义核心价值体系的内涵        ④有利于形成良好的社会风尚