Explanation:
According to the analysis, Molarity is amount mole per volume(1L). the amount in mole would be molarity × volume in litres.
0.500M × (250/1000)L= 0.125moles.
I hope this helps**
It's not really possible to tell longitudinal vs. transverse in this image as given. However, we can say that the waves labeled A are high-frequency (short wavelengths) while the waves labeled B are low-frequency (long wavelengths). So, this third answer choice would be correct here.