The question is incomplete. The complete question is :
Two loudspeakers are placed 1.8 m apart. They play tones of equal frequency. If you stand 3.0 m in front of the speakers, and exactly between them, you hear a minimum of intensity. As you walk parallel to the plane of the speakers, staying 3.0 m away, the sound intensity increases until reaching a maximum when you are directly in front of one of the speakers. The speed of sound in the room is 340 m/s.
What is the frequency of the sound?
Solution :
Given :
The distance between the two loud speakers, 
The speaker are in phase and so the path difference is zero constructive interference occurs.
At the point
, the speakers are out of phase and so the path difference is 
Therefore,




Thus the frequency is :


Hz
See this. I hope you find your answer
Answer:
Perm lasts longer
Explanation:
Cuz a chemical relaxer only lasts a few weeks and a perm lasts a few months hope this helps
Answer:
C:
Explanation:
either C or A but A seems unlikely after multiple attempts. Although the question doesn't make it clear whether the balance is electric either way it could be wrong in someway and seems to be the most likely.