One backing material used in groove welding is _____
a. plastic
b. an inert gas
c. vinyl
d. dross
b
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____ framing is one of the most difficult parts of wood light frame construction and requires skilled carpentry.
A. Ceiling B. Roof C. Wall D. Floor
The water make-up system takes its level measurement from the:
a. deaerator and steam generating drum b. economizer and deaerator c. mud drum d. superheated tubes
The friction between two surfaces is affected by all of these EXCEPT ________
A) Temperature B) Frictional material C) Surface finish D) Speed difference between the two surfaces
In most commercial air handlers
A) the blower draws the air across the coil B) the air passes through the unit twice: once for the blower and another time for the coil C) the blower and coil are located in separate component parts of the system D) the blower forces the air across the coil