how do you solve for the mean and error 4.34 < μ < 9.48

Astandard american eskimo dog has a mean weight of 30 pounds with a standard deviation of 2 pounds. assuming the weights of standard eskimo dogs are normally distributed, what range of weights would 99.7% of the dogs have? approximately 26–34 pounds approximately 24–36 pounds approximately 28–32 pounds approximately 29–31 pounds

This is so hard and it’s for a test

[15 points, algebra 2]simplify the complex fraction and find the restrictions.