Question 29 (1 point) Which of the following research situations would be most likely to use an independent-measures design? examine the long-term effectiveness of a stop-smoking treatment by interviewing individuals 2 months and 6 months after the treatment ends )examine the development of vocabulary as a group of children mature from age 2 to age 3 )compare the blood-pressure readings before medication and after medication for a group of patients with high blood pressure compare the language skills for 9th-grade boys relative to 9th-grade girls Question 30 (1 point) An independent-measures research study uses n = 15 participants in one group and / = 12 participants in a second group to compare two treatment conditions. What is the di value for the & statistic computed for the corresponding hypothesis test? O df = 27 O df - 25 O df = 26 O df - 24 Question 31 (1 point) Which of the following is not an assumption underlying the independent- measures & formula for hypothesis testing? )The two populations from which the samples are selected must have equal variances. The two populations from which the samples are selected must be normal. The observations within each sample must be independent. O The two samples must have equal sample sizes.Question 26 (1 point) A sample of n = 25 scores has a mean of M= 40 and a standard deviation of s = 10. What is the estimated standard error for the sample mean? SM - 2.5 OSM = 1 OSM = 2 O SM - 4 Question 27 (1 point) With a .05, the two-tailed critical region for a t test using a sample of n = 20 participants would have boundaries of Ot +2.086. Ot= +2.093. Ot= +2.080. Ot= +2.136. Question 28 (1 point) Consider a sample with M = 16 and s = 25. A researcher is testing the null hypothesis that u = 20. Which statement is correct? The treatment has a small effect size (Cohen's d). The treatment has a statistically significant effect. The treatment has a large effect size (Cohen's d). The treatment has a moderate effect size (Cohen's dd)