I attached the rest of your question in the image below.
We use the normal distribution density function f(z) to find the probability of a specific range of values.
Z= ((X-μ)/σ)
μ = 475
σ = 8
a) X< 470 ml
P[X<470] = P[Z<(470-475)/8] = P[Z<(470-475)/8] = P[Z<-0.625] = 0.2659
b) 6 pack with a mean of less than 470ml
Z = ((X-μ)/(σ/√n))
Z = (470-475)/(8/√6)
P [Z<-1.53] = 0.063
c) 12 pack with a mean of less than 470ml
Z = ((X-μ)/(σ/√n))
Z = (470-475)/(8/√12)
P [Z<-2.165] = 0.0152
