請教一下SAT試卷說明里兩句話的意思?數(shù)學(xué)：
數(shù)學(xué)： Unless otherwise specified, the domain of any function f is assumed to be the set of all real numbers x for which f(x) is a real number.
閱讀（一篇文章對應(yīng)兩個(gè)題目）：Answer the questions on the basis of what is stated or implied in each passage and in any introductory material that may be provided. (其中的introductory material ,在文章中并沒有,是不是說文章本身就是開頭的部分就是這個(gè)introd...)