单项选择题
A.forced circulating pump B.compressed air C.gravity tank D.bead tank
The abbreviation "TDS" about the potable water probably...
单项选择题The abbreviation "TDS" about the potable water probably means （）.
A.total dissolved solids B.temperature of distillation of sea water C.total dissolved sodium D.total delivery system
A condenser is a vessel in which（） is deprived of its l...
单项选择题A condenser is a vessel in which（） is deprived of its latent heat of vaporization and so changed to its liquid state.
A.sea water B.fresh water C.vapour D.gas
In more recent years, （） heat exchangers have frequentl...
单项选择题In more recent years, （） heat exchangers have frequently been employed for jacket water and oil cooling.
A.shell and tube type B.plate type C.coil type D.conical disc type
