If a taxpayer is unsuccessful in obtaining a tax refund in a suit heard in a U.S. Circuit Court of Appeal, the taxpayer may seek an appeal from:

a. the U.S. Tax Court

b. the U.S. Supreme Court

c. the Internal Revenue Service Appeals Division

d. the U.S. Circuit Court of Appeals for a different geographic region

e. all of the above

Which of the following may not be cited as published legal precedent to a court:

a. private letter ruling

b. internal revenue code

c. U.S. Supreme Court case

d. revenue ruling

e. both b and d