David is experimenting with electromagnetic waves. He has four different waves to study, wave A, wave B, wave C, and wave D. In wave A, distance between two corresponding points on adjacent waves is greater than that of wave B. In wave C, the number of waves that pass a fixed point in a given time is greater than that of wave D. Which wave has lower frequency, wave A or wave B?
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Answer: wave A

John is a an ophthalmologist in a local hospital. Today, he has seen two patients, patient A and patient B. Patient A had hyperopia, but patient B didn't have any issues with eyes. John would now treat the patient that have eye problem. Would patient A see faraway objects similarly or differently than patient B?
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Answer: similarly

David needs to purchase a camera for his photography class. He went to the local consumer electronics store to find himself a good camera. Two cameras caught his eye, camera A and camera B. Camera A had a very small pinhole, but camera B had larger aperture. David needs to decide which camera should he buy. Which camera would have higher beam power, camera A or camera B?
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Answer:
camera B