-9 - I do not understand this at all please help

On a particular day, the power used in a particular state (in thousands of megawatts) could be approximated by the function P(t) = 0.005244t3 + 0.1993r2 - 1.081t+ 13.57 where t is the number of hours since midnight, for O StS 24. Find any relative extrema for power usage, as well as when they occurred. Find the derivative of P(t). P'(t) = Find any relative extrema for power usage, as well as when they occurred. Select the correct choice below and, if necessary, fill in any answer boxes within your choice. O A- There are no relative minima. The relative maximum/maxima islare at the t-value(s) t= . (Use a comma to separate answers as needed. Type integers or decimals rounded to the nearest hundredth as needed.) O B- The relative maximum/maxima islare at the t-value(s) t= and the relative minimum/minima islare at the t-value(s) t= (Use a comma to separate answers as needed. Type integers or decimals rounded to the nearest hundredth as needed.) O C. There are no relative maxima. The relative minimum/minima islare at the tvalue(s) t= . (Use a comma to separate answers as needed. Type integers or decimals rounded to the nearest hundredth as needed.) O D. There are no relative extrema