State the total degrees of freedom for the followingt-tests. (If you need to use, enter INFINITY.)

(a)n=12

for a one-independent samplet-test

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(b)df₁=13,n₂=21

for a two-independent samplet-test

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(c) critical value = 1.645 for a one-tailed test,= 0.05

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(d) critical value = 63.657 for a two-tailed test,= 0.01

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