Construct a 90% confidence interval for the difference in population means. (Assume that the two populations from which the data came are normally distributed.) [Note: Formula (6.7.1) yields 17.2 degrees of freedom for these data.] (b) Why is it important that we assume that the two populations are normally distributed in part (a)

so, converting firstly the mixed fractions to improper fractions and then "adding".

a

step-by-step explanation:

80° is the measure of gh

step-by-step explanation:

circle f is congruent to circle j

we have two circle with center f and j.

both circles are congruent. the radius of the circle would be equal.

see the attachment for the circle.

we are given ∠efd ≅ ∠gjh

therefore, arc (ed) = arc (gh)     (∴ circle f is congruent to circle j)

but ∠dfe=80°=arc (ed)

therefore, arc (gh) = 80°

thus, 80° is the measure of gh