### QUESTION 6

Sara’s income is $500, the price of X is $6, and the price of Y is $4. Based on these prices and income, Sara buys 120 units of X and 70 units of Y. Call this combination of X and Y “bundle K.” At bundle K, Sara’s marginal rate of substitution is 2. Given these prices and income, what is Sara’s equilibrium consumption of X? Briefly explain your reasoning.

**QUESTION 7**

A firm’s marginal product of capital is twice its marginal product of labor; the price of labor is $6, and the price of capital is $3. Is the firm minimizing cost? If not, how can it reduce its cost? Explain.

Petram Company has two plants, one in the United States and one in Vietnam, and it cannot change the size of the plants or the amount of capital equipment. The hourly wage in Vietnam is $5, while the hourly wage in the United States is $20. Given current employment, the marginal product of the last worker in Vietnam is 100, and the marginal product of the last worker in the United States is 500. Based on this information, answer the following questions.

Is the firm maximizing output relative to