●A Bluetooth device can be either a master or a slave and any of the devices within a __(71)__can be the master.There is only one master and there can be up to __(72)__active slave devices at a time within a single network.In addition，a device may be a st

●A Bluetooth device can be either a master or a slave and any of the devices within a __(71)__can be the master.There is only one master and there can be up to __(72)__active slave devices at a time within a single network.In addition，a device may be a standby slave or a parked slave.There can be up to __(73)__ parked slaves.If there are already maximum number of active slaves，then a parked slave must wait until one of the active slaves switches to __(74)__mode before it can become active.Within a network，all __(75)__communications are prohibited.
（71）A．Wireless LAN
B．Wireless MAN
C．Cellular radio network
D．Piconet
（72）A．7
B．15
C．63
D．255
（73）A．127
B．255
C．511
D．1023
（74）A．master
B．standby slave
C．parked slave
D．active slave
（75）A．master-to-master
B．master-to-slave
C．slave-to-slave
D．slave-to-master