What would the mixed air temperature be for a system with 20% outdoor air if the outdoor temperature is 90°F and the return air temperature is 80°F?
A) 0.8 × 90°F =18°F; 18°F + 80°F = 98°F mixed air temperature
B) (90°F + 80°F) × 0.4 = 68°F
C) (90°F + 80°F)/2 = 85°F mixed air temperature
D) 0.2 × 90°F =18°F; 0.8 × 80°F = 64°F; 18°F + 64°F = 82°F mixed air temperature
D
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Which of the following is true when joining PVC conduit?
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Determine the gain v?/vi of the circuit in Fig. 5.90.
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