A pair of in-phase stereo speakers is placed side by side, 0.58 m apart...?

[Don'tcallmeKatie]

1. A pair of in-phase stereo speakers is placed side by side, 0.58 m apart. You stand directly in front of one of the speakers, 1.0 m from the speaker. What is the lowest frequency that will produce constructive interference at your location?
____________kHz


2. Two loudspeakers are placed at either end of a gymnasium, both pointing toward the center of the gym and equidistant from it. The speakers emit 255 Hz sound that is in phase. An observer at the center of the gym experiences constructive interference. How far toward either speaker must the observer walk to first experience destructive interference?

I've been working on my physics homework and these are the two questions that I simply cannot get. I've gotten 3 or 4 different answers for both of them, but none of them are right!

If you know how to do it, please explain!

Thank You!

[Unregistered]

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