Ineed trying to figure out what is the domain as well as the range and determine if it's a function or not

Brian, chris, and damien took a math test that had 20 questions. the number of questions brian got right is 14 more than the number of questions chris got right. damien correctly answered 2 less than the number of questions chris answered correctly. if brian and damien have the same score, which statement is true?

Credit card a offers an introductory apr of 3.4% for the first three months and standard apr of 15.7% thereafter,

Which expression is equivalent to (4 +6i)^2? ? -20 + 48i 8 + 12i 16 - 36i 20 + 48i