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The equation b=(10 dB) log (I/I₀), which defines the decibel, is sometimes written in terms of power P (in watts) rather than intensity I (in watts/meter²). The form b=(10 dB) log (P/P₀) can be used to compare two power levels in terms of decibels. Suppose that stereo amplifier A is rated at P=250 watts per channel, and amplifier B has a rating of P₀=45 watts per channel. (a) Expressed in decibels, how much more powerful is A compared to B? (b) Will A sound more than twice as loud as B? Justify your answer.