step90=[0 0.002 0.02 0.055 0.112 0.187 0.269 0.377 0.498 0.645 0.799 0.987 1.182 1.411 1.655 1.928 2.22 2.553 2.891 3.262 3.657 4.073 4.533 5.005 5.517 6.053 6.621 7.184 7.802 8.367 8.987 9.574 10.137 10.808 11.543 12.289 13.112 13.916 14.75 15.679 16.534 ];
a=[0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 74 76 78 80 ];
plot(a,step90);
