1.  Human ear can detect sound intensities of the order of W/m2.
A. 10-20
B. 10-13
C. 10-6
D. 10-3

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2. The unit of loudness is
A. phon
B. sone
C. decibel
D. mel

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3. Neper is decibel.
A. larger than
B. smaller than
C. equal to
D. none of the above

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4. When power ratios are expressed in dBm, the reference power is
A. 1 W
B. 1 mW
C. 1 IAW
D. none of the above

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5. In a superhet broadcast receiver, the frequency of local oscillatoris the incoming signal frequency.
A. higher than
B. lower than
C. equalto
D. none of the above

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6. High intermediate frequency in a superhet receiver
A. increases tracking problems
B. reduces adjacent channel rejection
C. improves selectivity
D. none of the above

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7. If the carrier of a 100% modulated A.M. wave is suppressed, the power saving will be percent.
A.50
B.67
C.75
D.80

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