Someone plz tell me when r we going to use this in life

y=mx+b

Choose all answers that apply: a) ab and a’b’ are one the same line. b) quadrilaterals abcd and a’ b’ c’ d’ have the same perimeters. c) points a and a’ have the same coordinates. d) none of the above

What is the value of the expression below? (81^2)^1/8

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.