Directions: Find the missing lengths in these problems below, in which A ABC VA DEF
1. AB = 8, BC = 14; DE = 12, EF = ?
2. AB = 4, AC = ?; DE = 1, DF = 9
3. AB = 12, AC = 18, BC = 15; DE = 8, DF = ?. EF = ?
NEED HELP ASAP

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.