X-7;x=3 evaluate the expression for the given value of the variable

The question is kind of confusing. if it's asking how many variations of answers can you give. then do 4^5 for your answer.this would be something like the first question could be a and the 2nd c or first b next c etc. if you can, ask the teacher for a better confirmation of what it's asking. if i'm assuming correctly what it's asking, it's 625 different variations.

The additive identity is 0 because when you add 0 to a number, you get the identical number as an answer.a + 0 = a