Given that the energy contains in doughnut is Q = 302
Calories
                                                                     Â
= 302x103 cal
                                                                       =
302x103 x4.19 J
                                                                       =
1265.38x103
JÂ Â Â Â Â Â Â Â Â Â
(Since 1 Calorie is equal to 1000 cal)
Total energy required to reach height h is Q = mgh
                                                           Â
h = Q /mg
                                                                =
1265.38x103 J /
75kg*9.8m/s2Â Â Â Â Â Â Â
                                                                =
1.7216x103 m
But height of the each step is h' = 22cm = 0.22m
Number of stairs that you climb is
                    N
= h /h'
                      Â
= 1.7216x103 m / 0.22m
                      Â
= 7.825x103
                      Â
= 7825 steps