Volume of the cylinder  of radius r and height h is given by the formula πr2h.  Using this formula, we will have , 540=πr2 (15). This can be solved for r as follows:

 

                                    r2= 540/ 15π

                                              =540/47.1

                                               =11.46

                                           r = 3.38

                         Hence,     Diameter will be 6.76 ft

                                                   ****