A simple calculation of the price elasticity of demand will yield – results depending on whether one considers the change as going from (Q1, P1) to (Q2, P2) or in the reverse direction. The midpoint method gives the same answer either way because it uses – price and – quantity as the basis for the – change calculations.

answer; i believe that the correct answer is (essential amino acids);

just put in mind that others aren't perfect. we all have problems that we feel makes us low of the low. but know that you are special and unique, that is what makes you out of this world : ). you might think and feel that others judge you, but mostly other people are scared if people judge them. just be happy, spend time with family, smile because that is the greatest medicine. a happy life. hope this : ))