Evaluation of the antioxidant activity of biologically active flavonoids using DPPH methodology

Please calculate the AA% for the results I obtained for Quercetin and plot the graphic for Quercetin. 

Please also answer the following 3 questions:

QUESTION 1

Give the order of potency for the assayed      flavonoids through the DPPH test based on their EC50 ranging from the      least potent to the most potent.

QUESTION 2

What do lower values for EC50 mean? 

QUESTION 3: 

Upload the graphic of AA% against concentration that      you obtained for Quercetin evaluated in the practical showing the best      regression line and the r square value calculated.