Weight of the dogs treated at a veterinary clinic are normally distributed

& have a mean (μ) of 36.2lbs and a standard deviation σ of 8lbs.

a) what is the probability that a dog weighs less than 26.2lbs 

b) what is the probability that a dog weighs less than 42.2lbs 

c) what is the probability that a dog weighs between 26.2 and 44lbs 

for the following 2problems, first find z (x = μ + z σ) 

d) the probability that all dogs weigh less than x1 lbs is 0.6700; what is the weight x1? 

e) the probability that all dogs weigh less than x2lbs is 0.1003; what is the weight x2? 

i know you guys could solve this with your eyes closed but would really love an explanation. thanks