n = 100 (slider from 0 to 200, step 1)
p = 0.3 (slider from 0 to 1, step 0.01)
m: n * p
s: sqrt(n * p * (1 - p))
a = BarChart((-m) / s, (n - m) / s, Sequence[Binomial[n, k] * p^(k) * (1 - p)^(n - k), k, 0, n])