Which channel is designated for VHF Digital Selective Calling？
A. Channel 70
B. Channel 06
Channel 13
D. Channel 16
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What is the minimum requirement of a GMDSS operator？
A. GMDSS operator license
B. Third officer license
C. General Radiotelephone Operator license and Radar Endorsement
D. General Radiotelephone license or First or Second Class Radiotelegraph license with GMDSS Radio Officer’s endorsement
以连续送进的焊丝做为电极和填充金属的焊接方法是()。
A. 焊条电弧焊
B. 熔化极气体保护焊
C. 鎢极氩弧焊
D. 等离子焊
What is defined as and area, excluding sea areas A1 and A2, within the coverage of an INMARSAT geostationary satellite in which continuous alerting is available？
A. Ocean Area Regions AOR-E, AOR-W, POR or IOR
B. Sea Area A3
C. Sea Area A4
D. Coastal and Inland Waters
What is defined as an area outside sea areas A1, A2 and A3？
AOR-E
B. AOR-W
Coastal and inland waters
D. A4
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