When using horizontal sextant angles of three objects to fix your position，an indeterminate position will result in which situation（）.

A . the ship is in a harbor B . the ship is at anchorage C . the ship is underway D . all of the above

A . left in the sunlight B . stowed wet C . folded frequently D . washed with soap and water

A .  j_login B .  j_get_user C .  j_login_check D .  j_get_security E .  j_security_check

A . frame monitoring B . radio scan C . self-healing D . client walkabout

A . the best fix is obtained by using a tangent bearing and a range B . and using two radar ranges for a fix，the objects of the ranges should be close to reciprocal bearings C . and using ranges，the most rapidly changing range should be measured last D . and crossing a radar range of one object with the visual bearing of a second object，the two objects should be 80°to 110°apart

A . HMAC-SHA B . HMAC-MD5 C . CBC-DES D . AES E . 3DES

A . The message can be directed to the desired location B . The message can follow the earth‟s curvature C . The quality of message can not be affected by climatic D . the range of the message extend and the quality of reception is improved

A . dwell-tachometer B . exhaust gas pyrometer C . fuel flow rate mete D . exhaust gas analyzer

A . when anchoring in the Mediterranean B . when docking stern to a berth C . when docking bow to a berth D . when anchoring in a strong current

A . Only when there is a chance of their being seen by rescue vessels B . At half-hour intervals C . At one-hour intervals D . Immediately upon abandoning the vessel

A .  j_user and j_id B .  j_id and j_password C .  j_users and j_password D .  j_user and j_password E .  j_login and j_password F .  j_username and j_password

A . displacement tonnage B . weight forces C . buoyancy forces D . environmental force

A . Immediately upon abandoning the vessel B . Only when there is a chance of their being seen by a rescue vessel C . At one hour intervals D . At half hour interval

A . Drape along brackets B . Leave in place while back loading cargo to save time C . Hang vertically in the paint locker D . All of the above

A、Low-speed flight only B、High-speed flight only C、Low-speed flight and high-speed flight

A、you want to say goodbye to someone B、you want to thank someone C、you want to greet someone D、you want to apologize to someone