Two waves that have (10 Points)
will add together to produce beats *
the same frequency
slightly different frequencies
different speeds
the same wavelength

slightly different frequencies

Explanation:

The alternate increase or decrease of sound produced by the interference of two sound waves of slightly  different frequencies is called ‘Beat’. The maximum beat frequency that a human ear can detect is 7 beats/sec.

This definition of the beats is clearly pointing out that the two waves whose frequencies are slightly different will add together to produce the beats.

Therefore, the correct answer will be:

slightly different frequencies

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