Solving a Question: I Thought it Was D!

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AI Thread Summary
The discussion centers around a question where the user initially believed the answer was D, but the book indicates it is A. The confusion arises from the user's understanding of wavelength and frequency conventions, specifically that longer wavelengths correspond to shorter frequencies, typically represented on the left. The user expresses frustration with the orientation of the attached question image due to technical issues. Clarification on the correct answer and the reasoning behind it is sought. The conversation highlights the importance of understanding wavelength and frequency relationships in solving such questions.
Peter G.
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Hi,

So, I attached the question below.

I thought the answer was D but the book says it is A.

I thought it was D because I thought, well, I don't know, by convention, longest wavelengths and thus shorter frequencies, are to the left.

Thanks!
 

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So sorry it is rotated. My computer refuses to rotate it!
 
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