单项选择题
A.easy/reliable
B.difficult/cheap
C.stable/compulsory
D.easy/expensive
单项选择题 In the COSPAS-SARSAT system distress signals are processed by（）and the resulting data are forwarded to（）through（）communication network.
单项选择题 The COSPAS-SARSAT system can provide distress alerts to the appropriate rescue authorities（）.
单项选择题 For COAPAS-SARSAT system,（）process the distress signal from EPIRB to determine its position and identity.