If a humidifier is used in a central-heating or air conditioning system, it is generally operated only when the ____.
a. heat exchanger is in operation
b. gas shutoff valve is open
c. blower is in operation
d. filter is clean
c. blower is in operation
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Indicate whether the statement is true or false
What is the purpose of the vehicle module scan report?
What will be an ideal response?
When a load is placed on a truck with a C-channel, ladder frame, which ONE of the following is true of the C-channel rails?
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What two fasteners are used with fiberglass duct?
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