I enter the code to the Mathematica as follows:

k = 40; T = 1; r = 0.08; sigma = 0.3; deta = 0;
d1 = {Log[s/k] + (r - deta + 0.5*sigma^2)*(T - t)}/sigma/Sqrt[T - t];
d2 = d1 - sigma*Sqrt[T - t];
n1 = CDF[NormalDistribution[0, 1], d1[[1]]];
n2 = CDF[NormalDistribution[0, 1], d2[[1]]];
c = s*Exp[-deta*(T - t)]*n1 - k*Exp[-r*(T - t)]*n2;
Manipulate[Plot[c, {s, 1, 70}], {t, 1/12, 11/12}]


But after I press "shift+enter", the maniputlate reult shows nothing. Any one know what I do wrong?