do one of the following as appropriate. (a) find the critical value za/2 (b) find the critical value ta/2 (c) state that neither the normal nor the t distribution applies. Confidence level 95% n=18 o is known population appears to be very skewed find the critical value a.ta/2=2.110 b.za/2=1.96 c. ta/2=1.740 d.za/2=1.645 e. neither normal nor t distribution Solution Given a=0.05, the critical value is t(0.025,df=n-1=17)=2.11 (from student t table) Answer: a.ta/2=2.110.