单项选择题
The part of the shipboard electrical system used to control the distribution of power to the branch circuits, is the （）.
A.bridge control panel B.disconnect links C.governor relay box D.main switchboard
单项选择题 A semiconductor is a material with a （）.
单项选择题 The sub-multiple prefix “micro” means （）.
单项选择题 A signal derived from a controlled function and returned to the initiating point is called a/an （）.
