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A loudspeaker emits sound at 60 d.B. A second loudspeaker, identical to the first, is placed at the same distance from you. Compute the combined intensity of the sound that reaches you, in dB. Hint: remember the property of logarithms log10 (A B) = log10 (A) + log10 (B) for two numbers A and B Number UnitsWhat is the minimal frequency that an electromagnetic wave should have in order to resolve an object 01 size 1 m? Give you result in Hz. Number Units