在奴隶社会，脑力劳动和体力劳动分工的出现（）。

LANs can be connected by using bridges, which operate in the(67).

A．data-link layer

B．Physical layer

C．network layer

D．transport layer

LANs can be connected by using bridges, which operate in the

A．physical layer

B．data link layer

C．network layer

D．transport layer

LANs can be connected by using bridges,which operate in the

A． physical layer

B．data link layer

C．network layer

D．transport layer

LANs can be connected by using bridges,which operate in the

A． physical layer

B．data link layer

C．network layer

D．transport layer

Which of the following is not a characteristic of LANs？

A．Allowing many computers to transfer information between themselves.

B．Moving large amounts of data at a speed of 50 million bits/sec.

C．Making computers run faster than they do before connected to a LAN.

D．Differing greatly from a distributed system in lots of ways.

A．eSATA

B．Bluetooth

C．SCSI

D．Ethernet

A．A.One TG consists of up to 16 TRXs

B．B.One TG can be connected to a maximum of 32 cells

C．C.A cell can be connected to one only

Which one of the followings is NOT the advantage of using electricity？

A．It can achieve the same values as using chemical elicitors.

B．It can be used time and again.

C．It can boost chemical production.

D．It has no adverse impacts on the growth of plants.