12. Beth's scores on the six Earth science tests she took this semester are: 65, 72, 84, 85, 68, 100, 95, 55, 85, 75, 100
For this population, how many scores are within one standard deviation of the mean?
A)7
B) 5
C)6
D)4

Astudent draws two parabolas on graph paper. both parabolas cross the x-axis at (–4, 0) and (6, 0). the y-intercept of the first parabola is (0, –12). the y-intercept of the second parabola is (0, –24). what is the positive difference between the a values for the two functions that describe the parabolas? write your answer as a decimal rounded to the nearest tenth