σ = 0.33 (slider from 0 to 5, step 0.01)
μ = 1.5 (slider from -5 to 5, step 0.1)
f(x) = (1 / ((σ * sqrt((2 * π)))) * exp(((-0.5) * ((x - μ) / σ)^(2))))
A = Point(xAxis)
B = Point(xAxis)
a = Integral(f, x(A), x(B))
b: x = μ
c: x = μ - σ
d: x = μ + σ