Marshall's mother buy's 2 boxes of granola bars each week. each box contains 8 granola bars if she continues buying 2 boxes each week, how many granola bars will she buy in a year (1 year= 52 weeks)

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