please help me with the questions below:

6. [-/1 Points] DETAILS LARCAAPCALC2 11.4.048.MI. MY NOTES Find the change in cost C for the given marginal. Assume that the number of units x increases by 5 from the specified value of x. (Round your answer to two decimal place Marginal Number of Units, x do _ 26,000 dx x2 * = 12 $B. [42 Points] LARCAAPCALC211.4.06D. Find the average value of the function on the interval. 1 E Find all xvalues in the interval for which the function is equal to its average value. [Enter your answers as a col Need Help? [0. 2] 9. [-1'1 Points] LARCAAPCALCZHAJJTD. Find the amount of an annuity with income function CU}, interest rate r, and term T. (Round your answer to tw: c{t}| = BRIDE], r = 3%, T: 15 years $ Z Need Help? 1|]. [-11 Points] LAREAAPCALCE 11.4.?4. You are given the rate of investment ddt. Find the capital accumulation over a seven-year period by evaluating ? Capital accumulation = E or D cit where (\"is the time in years. {Round 1Jurour answer to two decimal places.) _ 10,000: dt [1'2 + 2? $ Z Need Help?