Consider a normal distribution curve where the 85th percentile is at 20 and the 45th percentile is at 4. Use this information to find the mean, ( μ ), and the standard deviation, ( σ ), of the distribution.
a) ( μ = 12, σ = 2 )
b) ( μ = 14, σ = 3 )
c) ( μ = 16, σ = 4 )
d) ( μ = 18, σ = 5 )