根据首字母提示填写单词,补全下面的短文。
Betty is going to e____ herself during the M____ Day holiday. On the morning of 1st May she is going to g____ up late and then r____ a book. In the afternoon, she is going to do her h____ with her classmate.
(Ⅰ)若 AF→=2FB→ ,求直线AB的斜率;
(Ⅱ)设点M在线段AB上运动,原点O关于点M的对称点为C,求四边形OACB面积的最小值.
下列大洲中赤道、北回归线、南回归线都穿过的是( )