影响牙槽嵴吸收速率的局部因素是（）
A.失牙原因
B.失牙时间
C.局部骨质密度
D.是否经过牙槽嵴修整
E.以上都是
参考答案：E
下列命令中，哪个命令能为远程对象生成stub和skeleton
A．rmic
B．rmiregistry
C．rmid
D．serialver
Helen always helps her mother even though going to school ______ most of her day.
A．takes up
B．makes up
C．saves up
D．puts up
