A:are sending to
B:sending to
C:to be sent to
D:are sent to
若13a2m-5bn+1与﹣3ab3﹣n的和为单项式,则m+n=____
如图所示,渔民在叉鱼时,为了能叉到鱼,鱼叉应对准( )
人们到医院看病时,有时需要做血常规化验.医生判断患者是否贫血,是根据下列哪项的数值低于正常值而做出的( )