Consider the following cassava yield response functions to potassium (K) input in Cambodia Using traditional varieties: Y = 2,000+100K-0

Consider the following cassava yield response functions to potassium (K) input in Cambodia

Using traditional varieties:

Y = 2,000+100K-0.3K(squared)

MPP = 100 – 0.6K

Using the new cassava variety:

Y = 2500 + 160K – 0.4K(squared)

MPP = 160 – 0.8K

Y is yield of cassava (kg/ha), K is kg of potassium, and MPP is marginal physical product. Assume that the price of one kg of potassium costs 160 Riel and one kg of cassava sells for 4 Riel (where Riel is the Cambodian currency).

A farmer using traditional varieties, will choose what level of potassium to maximize profit?

a) 100

b) 50

c) 150

d) 10

e) 0