Most people can roll their tongues, but many can't. the ability to roll the tongue is genetically determined. suppose we are interested in determining what proportion of students can roll their tongues. we test a simple random sample of 400 students and find that 317 can roll their tongues. the margin of error for a 95% confidence interval for the true proportion of tongue rollers among students is closest to

Look at this system of equations. -3x + 3y = 12 y = x + 4 the solution set of this system is best explained by which of these statements? a) the graphs of the equations are the same line because the equations have the same slope and the same y-intercept. the system has infinitely many solutions. b) the graphs of the equations are parallel lines because they have the same slope but different y-intercepts. the system has no solution. c) the graphs of the equations are lines that intersect at one point because the equations have the same slope but different y-intercepts. the system has exactly one solution. d) the graphs of the equations are lines that intersect at one point because the equations have the same slope and the same y-intercept. the system has exactly one solution.