Do one of the following, as appropriate: (a) Find the critical value z a/2
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, (b) find the critical value t a/2
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, (c) state that neither the normal nor the t distribution applies. 98\%; n=7;σ=27; population appears to be normally distributed. t α/2=2.575
t α/2=1.96
z a/2=2.05
z a/2=2.33
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Do one of the following, as appropriate: (a) Find the critical value z a/2
​
, (b) find the critical value t a/2
​
, (c) state that neither the normal nor the t distribution applies. 90\%; n=10;σ is unknown; population appears to be normally distributed. t a/2=1.812 za/2=1.383 t a/2=1.833 z a/2=2.262