中厚皮片包含的皮肤结构有（）
A.表皮
B.表皮及大部分真皮
C.表皮及真皮
D.表皮、真皮及皮下组织
E.表皮、真皮及少量皮下组织
参考答案：B
所谓( )用地，是指一种以营造建(构)筑物为目的的工程用地的总称。
A．开发
B．工业
C．商业
D．建设
Packet-switching wireless networks are preferable (41) when transmissions are (42) because of the way charges are (43) per packet. Circuit-switched networks are preferable for transferring large files or for other lengthy transmissions because customers are (44) for the (45) of time they use the net-work.
A．charged
B．fined
C．free
D．controlled
