一船从甲港顺水而下行到乙港，马上又从乙港逆水行回甲港，共用了8小时，已知顺水每小时比逆水多行20千米，又知前4小时多行60千米，那么，甲、乙两港-But not have other words well, women are turning off the lamp, but closed the light touch, it must be very comfortable! Especially girls that plentiful full chest, if give yours