When ____ circulators are used, the header they connect to should be located close to and just downstream from the point where the expansion tank is connected.
a. multiple zone
b. variable speed
c. hydraulic
d. single zone
a. multiple zone
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? Identify and state the historical significance of the Wade-Davis Bill.
What will be an ideal response?
?It is important that tack welds be made _____________________________ so that they do not become weld defects in the finished weld.
Fill in the blank(s) with the appropriate word(s).
The last step after replacing a defective CV boot is to ________
A) Separate the CV joint before installation B) "Burp" the boot C) Lubricate the CV joint with chassis grease D) Mark the location of the boot on the drive axle shaft
A traffic accident causes traffic to come to a halt in an underwater tunnel. The people in their vehicles allow their engines to idle. There are 100 vehicles stopped in the tunnel; assume their vehicle engines emit on average 0.269 g/min of VOC (aldehyde), 3.82 g/min CO, and 0.079 g/min NOx. The tunnel is long and narrow with a height of 10 m, a width of 25 m, and a length of 0.5 km. Assume the ambient air concentrations of CO, VOCs, and NOx are small. The mean air velocity through the tunnel, when traffic stops, is limited to 0.2 m/s.
a. Assuming traffic remains halted long enough for the concentration carbon monoxide, nitric oxides, and hydrocarbons in the canyon to reach steady state, what would the expected concentrations of carbon monoxide, nitric oxides and hydrocarbons be in ppmv in the tunnel? b. Do the CO and NOx concentrations exceed NAAQS? c. Does the CO concentration exceed the OSHA’s permissible exposure limit (PEL)? What will be an ideal response?