For a normal distribution, verify that the probability between (a) and +

For a normal distribution, verify that the probability between

(a) μ − σ and μ + σ equals 0.68.

(b) μ − 1.96σ and μ + 1.96σ equals 0.95.

(c) μ − 3σ and μ + 3σ equals 0.997.

(d) μ − 0.67σ and μ + 0.67σ equals 0.50.