Four chemicals are to be blended to create one bag of fertilizer, the price of chemical A per pound is 0.2 dollars, per pound of chemical B is 0.35 dollars, per pound of chemical C is 0.4 dollars and per pound of chemical D is 0.3 dollars. One bag of fertilizer weighs 40 pounds. It is required that the constitution of chemical A and B are at least 20% of the blend. Chemical D cannot be less than 10% of the blend. Chemical B and C cannot exceed 50% of the blend. Determine the blend level of each chemical to minimize the cost of one bag of fertilizer. Use excel solver to solve this problem and answer the following questions.

2.1 What is the minimum cost of one bag of fertilizer? Report only numerical value.

2.2 How many pounds of chemical B should be in one bag of fertilizer?