Answer:
Lens and focal point is the correct answer.
The air molecules in the compressions of the second wave are denser, so the sound is louder.
<h3>What is a sound wave?</h3>
Sound waves are longitudinal waves that travel through a medium like air or water.
In a closed room, Noah and Nina are sitting 15 m apart.
As Noah says the same sentence twice, Nina does not hear the sound the first time but she does hear the sentence the second time.
This happens as the air molecules in the compressions of the second wave are denser. As a result, the sound is louder.
The correct option is ''The air molecules in the compressions of the second wave are denser, so the sound is louder''.
Learn more about the sound wave here:
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<span>This was one of the old regents. I didn't get this at first glance too so I searched for it and I got this site. lol. I know what to do now. To get a higher boiling point, you have to find which solution has the most moles. Since SO4, PO4, and NO3 are all polyatomic ions, they only count as one mole. </span>
The chemical formula for methane is CH4