20. The demand lnctions for two products are given below. p1, p2, q1,and 12 are the prices (in dollars) and quanties for products 1 and 2. q1=350+p1+2p2 9'2 =225+P1 +1); a. Are these two products complementary goods or substitute goods? b. What is the quantity demanded for each when the price for product 1 is $20 per item and the price for product 2 is $30 per item?I c. Write a function R(p1,p2)that expresses the total revenue from these two products. d. Find the price and quantity for each product that maximizes the total revenue