600 500 488 503 517 525 529 536 542 434 462 400 Critical reading SAT 300 200 100 0 0-20 40-60 80-100 120-140 160-200 Family income ($1,000) This data can be modeled by S(x) = 540 - 126(0.987)* where S(x) is the average critical reading SAT scores of students whose household income is x thousands dollars per year. Numerically estimate lim S(x), and interpret the answer. X-+00