A study had subjects read a passage and take a comprehension test on what they read. The researchers randomly assigned subjects so that half of them listened to music with lyrics while reading, while the other half listened to music without lyrics while reading. Here are their scores on the comprehension test: Music with lyrics 75 62 65 41 54 Music without lyrics 64 71 88 77 62 The researchers want to test if these results represent a significant difference in the average score between the groups. Assume that the necessary conditions for inference were met. Which of these is the most appropriate test and alternative hypothesis?

There are two major tests of readiness for college: the act and the sat. act scores are reported on a scale from 1 to 36. the distribution of act scores in recent years has been roughly normal with mean µ = 20.9 and standard deviation s = 4.8. sat scores are reported on a scale from 400 to 1600. sat scores have been roughly normal with mean µ = 1026 and standard deviation s = 209. reports on a student's act or sat usually give the percentile as well as the actual score. the percentile is just the cumulative proportion stated as a percent: the percent of all scores that were lower than this one. tanya scores 1260 on the sat. what is her percentile (± 1)?