b1) option a)
b2) option A)
c1)
alpha,α = 0.05
estimated slope= 0.8372
std error = 12.3668
Df = 17
t critical value = 2.110 [excel function:
=t.inv.2t(α,df) ]
margin of error ,E = t*std error = 2.110
* 12.3668 =
26.0917
95% confidence interval is ß1 ± E
lower bound = estimated slope - margin of error =
0.8372 - 26.0917 =
-25.25
upper bound = estimated slope + margin of error =
0.8372 + 26.0917 =
26.93
(-25.25 , 26.93)
c2) option c)
d1) option c)
d2) option a)
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