单项选择题
A.overboard B.a bilge well C.a slop tank D.a hot well
For the intermediate condition, thermostats must be cor...
单项选择题For the intermediate condition, thermostats must be correctly set （）.
A.by trial and error B.by and large C.automatically D.very easily
Most air conditioning units have （） for adjusting the r...
单项选择题Most air conditioning units have （） for adjusting the ratio of recirculated fresh airCare must be taken not to reduce the fresh air so that stuffiness or smells arise.
A.catch plates B.dampers C.regulating valves D.fans
In extreme weather conditions, either hot or cold, cont...
单项选择题In extreme weather conditions, either hot or cold, control of the air conditioning plant presents （） difficulties.
A.few B.little C.a little D.less
