We say that 3(5x + 1) is equivalent to 3 ⋅ 5x + 3 ⋅ 1, and 10x − 3x is equivalent to 7x. In a few sentences, explain the steps you would take to simplify this expression 2(5x + 4) − 3x + 1

Arandom sample of n = 25 observations is taken from a n(µ, σ ) population. a 95% confidence interval for µ was calculated to be (42.16, 57.84). the researcher feels that this interval is too wide. you want to reduce the interval to a width at most 12 units. a) for a confidence level of 95%, calculate the smallest sample size needed. b) for a sample size fixed at n = 25, calculate the largest confidence level 100(1 − α)% needed.