Problem 3. Two stationary speakers (call them speaker 1 and speaker 2) are a distance d = 2m apart. The sound produced is 550Hz and both speakers have an average power of 400W. Assume air temperature is 20C. Alice stands equidistant from each speaker but a perpendicular distance x = 20m to the right. a) Suppose the speakers have the same initial phase, 0, but speaker 1 is turned on 2.001s before speaker 2. What kind of interference will Alice observe? b) Again suppose speaker 1 is turned on first, this time 18.191s before speaker 2. Additionally, the bottom speaker begins with a different initial phase, 1. If Alice observes constructive interference at her location, what is the initial phase difference, 01-00A6? c) Now suppose both speakers are turned on at the same time with the same initial phase. Alice walks parallel the two speakers from her initial location. How far must Alice walk until she observes destructive interference for the second time? d) Someone changes the speaker settings and there is a new but unknown frequency. In addition, speaker 2 begins a quarter cycle ahead of speaker 1. Alice goes back to her initial location and again walks parallel the two speakers. Alice hears destructive interference after walking 5m. What is the new frequency? e) If the waves constructively interfere at Alice's initial location, what sound level will she hear? Bob shows up and hears 10dB while standing directly to the right of Alice. How far is he from Alice?