题目

American schools do not have separate classes for boys and girls. If boys want to cook or to sew, they can learn these things in classes that are no longer just for girls. If girls want to repair cars, they can now learn this in school. Most students like to have boys and girls on the same baseball team.Many boys and girls dress alike in school. They wear blue jeans and sport shirts. Some have long hair and some have short hair. Sometimes a boy has longer hair than a girl.Even the language is different. Students learn to say fire fighter instead of fireman, police officer instead of policeman,若△ABC的两个内角α，β满足cosα•cosβ＜0，则此三角形为（ ）A．锐角三角形B．钝角三角形C．直角三角形D．以上均有可能