Please help pic is below

Which of the following statements uses the multiplicative identity?

One-third of the people from country a claim that they are from country b, and the rest admit they are from country a. one-fourth of the people from country claim that they are from country a, and the rest admit they are from country b. in a combined census of the two countries, one-half of the total claimed to be from a. what is the ratio of the populations of country a to that of country b.

When the ball has traveled a distance of

If f(x) = 2x + 8 and g(x) = x4, what is (gº)?