​Two Separate Samples Are Being Used to Estimate the Difference

Multiple Choice

​Two separate samples are being used to estimate the difference between population means for two treatment conditions.Which of the following would produce the widest confidence interval?

A) ​n₁ =n₂ = 10 with a pooled variance of 10
B) ​n₁ =n₂ = 10 with a pooled variance of 100
C) ​n₁ =n₂ = 20 with a pooled variance of 10
D) ​n₁ =n₂ = 20 with a pooled variance of 100