Treatment Placebo A study was done using a treatment group and a placebo group. The results are shown in the table. Assume that the two samples are independent simple It P1 P2 random samples selected from normally distributed populations, and do not assume that the population standard deviations are equal. Complete parts (a) and n 31 36 (b) below. Use a 0.05 significance level for both parts. i 233 2.68 s 0.87 0.56