For each of the following situations, calculate the degrees of freedom \((d f)\) and determine the critical values of \(t\).

a. \(N=10 ; \mathrm{a}=.05 ; \mathrm{H}_{1}: \mu eq 5\)

b. \(N=20 ; \mathrm{a}=.05 ; \mathrm{H}_{1}: \mu eq 5\)

c. \(N=10 ; \mathrm{a}=.01 ; \mathrm{H}_{1}: \mu eq 5\)

d. \(N=20 ; \mathrm{a}=.01 ; \mathrm{H}_{1}: \mu eq 5\)

e. \(N=10 ; \mathrm{a}=.05 ; \mathrm{H}_{1}: \mu>5\)

f. \(N=20 ; \mathrm{a}=.05 ; \mathrm{H}_{1}: \mu>5\)

g. \(N=28 ; \mathrm{a}=.05 ; \mathrm{H}_{1}: \mu eq 5\)