如图，已知矩形ABCD，一条直线将该矩形ABCD分割成两个多边形，若这两个多边形的内角和分别为M和N，则M+N=____． 

辛弃疾《木兰花漫》是一首“送月”诗词，其中有一句说道：“是别有人间，那边才见，光景东头?”大意是：当这边月儿西落时，那边的人们是不是正看见明月东升?对此王国维评论说：“词人想象，直悟月轮绕地之理，与科学家密合，可谓神悟。”这里的“神悟”         

北半球西风气流受青藏高原阻挡，分为南北两支，冬季，西风气流南移，其南支气流沿青藏高原南缘向东移动，带来暖湿气流，读图，回答下面小题。

读“亚洲东部某时刻等压线(单位：百帕)分布图，”完成下列各题。

根据短文内容, 回答下列问题。
    I am Helen. I study in the No.1 Middle School now. There are forty-five students in my class. All of the students like to travel(旅游). Eight students like to travel by plane, because they think it is fast. It only takes about two hours to travel by plane from Beijing to Shanghai. But some students think taking a plane is too expensive. Twenty-two students usually travel by train. The trains are very fast, but they are cheaper (更便宜). And they can see interesting things through the windows. Fifteen students love to travel by car. Their parents drive them to some beautiful places. They can have a good time with the family. Do you know how I like to travel? I'm one of the twenty-two students.