9.What is the ratio of the actual water-vapor pressure of the air to the saturated water-vapor press
28.下列何種閥必須於瞬間全開或全關?(A)安全閥(Safety valve)(B)減壓閥(Pressure reduction valve)(C)洩壓閥(Pressure relief valve)
31.量測船舶油櫃或爐水液面位置時,係運用該液體性質中那一種物理量變化之差異來作檢測?(A)液體溫度變化量所致的壓力變化(B)液體流量變化量所致的壓力變化(C)液面高度變化量所致的壓力變化(D)液面瞬