Soot forming in the heat exchanger can be caused by:

A) Excessively high combustion temperatures. B) The presence of coal tar in the gas.
C) Too much air in the gas—air mixture. D) Too much gas in the gas—air mixture.


D

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What are the functions of the xylem and phloem?

What will be an ideal response?

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A presently owned machine has the projected mar­ket value and M&O costs shown below. An outside vendor of services has offered to provide the service of the existing machine at a fixed price per year. If the presently owned machine is replaced now, the cost of the fixed-price contract will be $33,000 per year. If the presently owned machine is replaced next year or any time after that, the contract price will be $35,000 per year. Determine if and when the defender should be replaced with the outside ven­dor using an interest rate of 10% per year. Assume used equipment similar to the defender will always be available, but that the current equipment will not be retained more than three additional years.

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A bolt that is threaded into a casting is often called a ________

A) Cap screw B) Stud C) Block bolt D) Crest bolt

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Why are explosion-proof motors not normally used on standard equipment?

A. They are too large. B. They are too noisy. C. They are too expensive. D. They cannot be replaced.

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