Fill in the blanks:
1. Suppose this firm is using capital and labour such that the MP Subscript Upper K is equal to 90 and the MP Subscript Upper L is equal to 180. If the prices per unit of capital and labour are ?$5 and ?$30, respectively, this firm _____(is not minimizing, is minimizing) its costs. The following substitution should be? made ____(no substitution is required, use more L and less K, use more K and less L)