Give a 99.5% confidence interval, for μ1−μ2μ1-μ2 given the following information. n1=30n1=30, ¯x1=2.58x¯1=2.58, s1=0.316s1=0.316 n2=40n2=40, ¯x2=2.68x¯2=2.68, s2=0.988s2=0.988  blank ± blank   Rounded to 2 decimal places.

A random sample of nn measurements was selected from a population with unknown mean μμ and standard deviation σσ. Calculate a 90% confidence interval for μ for each of the following situations: (a)    n=90, x¯¯¯=27, s=3.92n=90, x¯=27, s=3.92                 ≤μ≤ (b)    n=75, x¯¯¯=48.1, s=3.72n=75, x¯=48.1, s=3.72                      ≤μ≤  (c)    n=90, x¯¯¯=67.7, s=4.12n=90, x¯=67.7, s=4.12               ≤μ≤ (d)    n=105, x¯¯¯=100.3, s=3.21n=105, x¯=100.3, s=3.21                   ≤μ≤