If the illumination from a point source 4 ft. above a surface is 100 foot-candles, what will be the illumination level if the source is raised to 8 ft.?

A) 10 foot-candles.
B) 20 foot-candles.
C) 50 foot-candles.


A) 10 foot-candles.

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Explain why testing and inspection of materials may be required and how it is accomplished.

What will be an ideal response?

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The layout-crew hand signal shown in the figure below indicates _____.



a. turning point
b. use long rod
c. observation completed
d. move up

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PROBLEM 3.161 Two solid brass rods AB and CD are brazed to a brass sleeve EF. Determine the ratio for which the same maximum shearing stress occurs in the rods and in the sleeve.

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The standard diametric clearance between bolt and flange-hole is _________.

Fill in the blank(s) with the appropriate word(s).

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