Which of the following must never be used as a grounding electrode?
a. a metal underground gas piping system
b. a metal in-ground support structure
c. a ground ring
d. a metal underground water pipe in direct contact with the earth for 10' (3 m)
a. a metal underground gas piping system
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The effect of temperature on liquid viscosity is generally:
a. viscosity increases as temperature decreases b. viscosity decreases as temperature decreases c. viscosity increases as temperature increases d. viscosity is not affected by temperature
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Our country lies in a temperate zone
Indicate whether the statement is true or false
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Genetic engineering involves the expression of new proteins
Indicate whether the statement is true or false
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Alkaloid
What will be an ideal response?
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