For the years from 2001-2010, the number of americans traveling to other countries by plane
can be represented by the polynomial function a(t) = 20t^4 – 428t^3 + 2760t^2 – 4320t + 33,600,
where a is the number of thousands of americans traveling abroad
by airplane and t is the number of years since 2001. in which year
were there 40,000,000 americans traveling abroad? use the
rational root theorem to find your answer.
(hint: consider the function's domain and range before finding all
possible rational roots.)

Isabel graphed the following system of equations. 2x – y = 6 y = -3x + 4 she came up with the solution (2,-2). what were the 3 steps she did to get that solution? (make sure they are in the correct order)

Which of the following is closest to 32.9 x 7.5? a: 232 b: 259 c: 220 d: 265

Two researchers are attempting to create a new psychotherapy protocol that more reduces panic attacks. they believe that they have succeeded and are now in the clinical trial period of their protocol's development. they are working with several cohort groups, some of which have been through the new protocol, while others have done the standard protocol currently recommended. if these researchers are interested in evaluating the difference in the percentage of test subjects who successfully decreased their panic attacks in 2 months on the new protocol versus the percentage of test subjects who successfully decreased their panic attacks in 2 months with the traditional protocol, which of the following statistical tests would be most appropriate? a. analysis of variance (anova) b. correlation c. chi-square test d. paired t-test e. independent t-test