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1)You are given a sample size n = 28. You are asked for a 98% confidence interval. What value of t or z do you use?

2)You are given a sample size n = 47. You are asked for a 90% confidence interval. What value of t or z do you use?

3)You are given a sample size n = 64. You are asked for a 70% confidence interval. What value of t or z do you use? Enter only the value, not the letter t or z. Enter only the value, not the letter t or z.