Sodium-24 is a radioactive substance used for medical purposes. Suppose that a patient is injected with sodium-24 and the amount of sodium-24 in the patient's body in milligrams after t hours is given by S(t) = 5e–0.35t. What is the half-life of sodium-24?

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