Agroup of students attend a math club. half of the students are boys and 4/9 of the boys have brown eyes. what fraction of the group are boys with brown eyes?

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

Use stokes' theorem to evaluate c f · dr where c is oriented counterclockwise as viewed from above. f(x, y, z) = xyi + 5zj + 7yk, c is the curve of intersection of the plane x + z = 8 and the cylinder x2 + y2 = 81.

Solve this system of equations: y=x2-3x + 12 y=-2x+14 4. substitute the values of x, -1 and 2, into either origina equation to solve for the values of y. what are the solutions of the system of equations?