What is the area of parallelogram rstu?
а
со
•
ф
24 square units
26 square units
32 square units
38 square units
о
-6-5-4-3-2-1, 1 1 2 3 4 5 6
x

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.