Which EPIRB transmits a distress alert that is received and relayed by an INMARSAT satellite?（）

A . Encryption B . Minimal signal loss C . Bandwidth limits D . No EMI

A . approved by the CCS B . designed for float free，automatic activation C . operated on 121.5/243 MHz D . operated manually

A . is primarily designed for vessels operating up to 50 miles offshore or on foreign waters B . transmits a signal that can be detected by satellite C . must be manually activated D . operates in the medium and low frequency band

A . Distress messages should first be transmitted on 2182 kHz B . Channel 16 (156.8 MHz) may be used for distress messages C . If no answer is received on the designated distress frequencies，repeat the distress call on any frequency available D . It is advisable to follow a distress message on 2182 kHz by two dashes of 10 to 15 seconds duratio

A . operates on both military and civilian aircraft distress frequencies B . transmits both an alerting signal and a homing signal C . must be the float free type and automatically activated D . operates with a greater output of signal power

A . RTP multiplexing is used to keep multiple phone conversations separate B . RTP provides end-to-end delivery services for voice traffic. C . UDP is used to ensure a reliable transmission from sender to receiver. D . RTP is used to provide resource reservation for the voice stream. E . UDP provides multiplexing of multiple phone conversations.

A . after broken links are re-established B . in an improperly implemented redundant topology C . when upper-layer protocols require high reliability D . during high traffic periods E . when a dual ring topology is in use

A . indicate the ship in distress that the alert has been received B . alert ships in the area of a distress incident that a distress has occurred C . inform other coast station of distress incident D . repeat the distress alert in 5 minute

A . a distinctive signal B . the Morse Code signal for SOS C . a computerized voice announcement of Mayday D . your vessel's International Radio Call Sig

A . every station in one chain to transmit at the same time B . each station to transmit without reference to another station C . on-line transmission of single-line transmitters at the same time D . each station to only depend on the master for synchronization and signal ratio

A . orbiting satellites in space B . commercial radio stations C . private，commercial，and military aircraft D . ordinary radio statio

A . use English language B . always use the International Code C . preface it by the word SOS D . follow the transmission with the radio alarm signal

A . On the Ship Station License B . On the side of the EPIRB transmitter C . In the radio log D . On the Certificate of Inspectio

A . submarine EPIRB B . safety EPIRB C . ship EPIRB D . survival craft EPIRB

A . Encryption B . Bandwidth limits C . Minimal signal loss D . No EMI

A . standardization B . conversion C . encapsulation D . synchronizatio

A . entstat -v B . netstat -i C . entstat -aon D . netstat -na

A .  The transmitted signal from the AP arrives at the client at slightly different times resulting in  phase shifting. B .  If signal 2 is close to 360 degrees out of phase with signal 1， the result is essentially zerosignal  or a dead spot in the WLAN. C .  Multipath interference is less of an issue when using a DSSS technology because multipath is  frequency selective. D .  If signal 1 is in phase with signal 2， the result is essentially zerosignal or a dead spot in the  WLAN. E .  Multipath interference is solved by using dual antennas.

A . Before sending traffic, it must first join  multicast group 239.1.1.1 by sending an IGMPv2 membership report to the default router on the local subnet. B . It must send an IGMPv2 Request to Send  packet and then wait for an IGMPv2 Clear to Send packet from the IGMPv2 querier router on the local subnet C . It may begin transmitting multicast traffic to the group only when there is no other host transmitting to the group on the local subnet. D . It may transmit multicast traffic to the group at any time.&e

A . root guard B . loop guard C . BPDU guard D . UDLD E . BPDU skew detectio

A．BCCH B．SCH C．RACH