Answer:
a. U.S. wages will be higher than U.K. wages.
Step-by-step explanation:
Wages, which are the factor price for labor, depend on the marginal productivity of labor.
In other words, workers are paid in proportion to the amount of additional output they produce.
In this case, the marginal productivity of a U.S. worker (10 tons of steel, or 20 tons of chemicals) is higher than the marginal productivity of an U.K. worker (5 tons of steel or 15 tons of chemicals), for this reason, the U.S. worker will be paid more than the U.K. worker.