If a sample has 20 observations and a 90% confidence estimate for is needed, the appropriate t-score is ____.
A)	2.120
B)	1.746
C)	2.131
D)	1.729
Answer:D
If a sample has 20 observations and a 90% confidence estimate for is needed, the appropriate t-score is ____.
A)	2.120 B)	1.746 C)	2.131 D)	1.729