USAco is a domestic corporation that manufactures products in the U.S.  for distribution in the U.S. and abroad. During the current year, USAco  derives a pre-tax profit of $10 million, which includes $1 million of  foreign-source income derived from a country X sales office that is  considered an unincorporated branch for U.S. tax purposes. The country X  corporate income tax rate is 50% and the U.S. tax rate is 35%
1.What would be the worldwide effective tax rate on the $1 million of  foreign profits, assuming the U.S. taxes the worldwide income of  domestic corporations, but allows an unlimited credit for foreign income  taxes?
 
2.What would be the worldwide effective tax rate on the $1 million of  foreign profits, assuming the U.S. allows a credit for foreign income  taxes, but the credit is limited to the U.S. tax attributable to  foreign-source income?
 
3.How would your answer to part (b) change if the foreign tax rate was 30% rather than 50%?