A sample of 36 paired observations generates the following data:d

d

= 2.3 ands

2

D

s

D

2

= 4.6. Assume a normal distribution.(You may find it useful to reference the appropriate table:z tableort table)

a.Construct the 95% confidence interval for the mean difference_D.(Round intermediate calculations to at least 4 decimal places and final answers to 2 decimal places.)

b.Using the confidence interval, test whether the mean difference differs from zero.

• There is evidence that the mean difference differs from zero.
• There is no evidence that the mean difference differs from zero.