31. What will occur when two dissimilar metals are electrically coupled in the presence of an electrolyte such as sea water?
(A) General corrosion
(B) Galvanic corrosion
(C) Crevice corrosion
(D) Selective-phase corrosion

27. Which type of marine propulsive engine can offer the advantages of low weight and space requirements? (A) Diesel engine (B) Steam turbine engine (C) Gas turbine engine (D) Steam reciprocating engine

28. 軸向活塞式泵亦稱威廉珍妮泵是利用下列何者調整輸出量？ (A) 傾斜箱 (B) 單向閥 (C) 圓弧溝槽 (D) 孔閥

29. The products of combustion of marine fuels include sulfur dioxide, which, when combined with water vapor, forms acids such as the sulfurous acid and sulfuric acid. These acids cause cold-end corrosion if allowed to condense on boiler components of flue-gas ducting. Therefore, in order to prevent the cold-end corrosion, which action is not to be taken? (A) To ensure the temperature of exhaust gas is always above the condensation temperature level. (B) To install more heat exchangers in the flue-gas ducting so that the temperature of exhaust gas is further reduced. (C) To prevent any chemical process that formulates the acid within the boiler components of fluegas ducting. (D) To ensure there is no water-vapor condensate formed within the flue gas by controlling the flow temperatures in the flue-gas ducting.

30. 多級空氣壓縮機的卸載裝置一般裝在何處？ (A) 氣缸蓋上 (B) 進氣管上 (C) 排氣管上 (D) 中間冷卻器上

32. 推進器在水中，每旋轉一圈之前進距離可稱為下列何者？ (A) 2個螺距 (B) 1.5個螺距 (C) 1個螺距 (D) 0.5個螺距

33. 柱塞式油壓泵常使用於何種船舶機械上？ (A) 舵機 (B) 吊貨機 (C) 救生艇吊放機 (D) 主機潤滑油輸送機

34. 何種閥應設於液壓泵至蓄壓器的管路間？ (A) 定量閥 (B) 止回閥 (C) 減壓閥 (D) 節流閥

35. 下列何者不屬於軸馬力計的型式之一？ (A) 光學式 (B) 張線振動式 (C) 離心式 (D) 相位差式

36. What are the documents to be examined by the on-board port state control officer?①Tonnage certificate ②Shipboard oil pollution emergency plan ③Oil record book ④Financial report (A) ①②③ (B) ②③④ (C) ①③④ (D) ①②④

37. 下列何者為噴射泵所不具備的特點？ (A) 無運轉部件 (B) 結構簡單 (C) 工作效率高 (D) 抽吸能力較強