Need help THERE ARE TWO SEPARATE QUESTIONS IN THE VERY FIRST SCREENSHOT I HAVE TO SOLVE FOR (f[g(x)) and g(x). thank you if you can help.

To test an individual's use of a certain mineral, a researcher injects a small amount of a radioactive form of that mineral into the person's bloodstream. The mineral remaining in the bloodstream is measured each day for several days. Suppose the amount of the mineral remaining in the bloodstream (in milligrams per cubic centimeter) t days after the initial injection is approximated by C(t) = =(4t+ 4) ". Find the rate of change of the mineral level with respect to time for 7.5 days. The rate of change of the mineral level with respect to time for 7.5 days is approximately milligrams per cubic centimeter per day. (Round to two decimal places as needed.)Find fig(x)] and g[f(x)]. f(x) = 3x2-5; g(x)= - X fig(xx)] =