A Process to Extract Pigment from Sunflower Seeds Involves Washing

Multiple Choice

A process to extract pigment from sunflower seeds involves washing the sunflower heads in heated water. Suppose the percentage of pigment that can be removed from the sunflower head by washing for 20 minutes is percent, where r is the amount of milliliters of water per gram of sunflower used for washing and is the water temperature. Is the critical point of P a maximum, minimum or saddle point?

A) maximum
B) minimum
C) saddle point
D) cannot be determined