How can amani use the trend line to check the reasonableness of her answer? a. she should expect the slope to be negative because the line tilts down moving from left to right on the graph. b. she should expect the slope to be negative because more points are below the line than above the line. c. she should expect the slope to be positive because the line has a positive  y-intercept. d. she should expect the slope to be positive because all the plotted points have positive coordinates