根据题意得:∠CAM=∠DCA=45°,∠CBM=∠DCB=30
下列与“食物的消化和吸收”有关的内容中,正确的是( )
若 2×8n×16n=222 ,则n=____
When I got home for my birthday from school, no one was at home, and this made me _______.
血量相对稳定,有利于人体维持正常的生理活动,一个人一次失血超过多少回危及生命( )