Suppose a sample of 49 paired differences that have been randomly selected from a normally distributed population of paired differences yields a sample mean of

d=5.3d=5.3

and a sample standard deviation ofs_d= 7.5.

(a)Calculate a 95 percent confidence interval for_d=₁-₂.(Round your answers to 2 decimal places.)

Confidence Interval = [ ______ , _________]

(b)Test the null hypothesisH₀:_d= 0 versus the alternative hypothesisH_a:_d 0 by settingequal to .10, .05, .01, and .001. How much evidence is there that_ddiffers from 0?

t - 4.947

Reject H0 at a equal to ________, _________ evidence that u1 differs from u2