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In a study conducted by some Statistics students, 59 people were randomly assigned to listen to rap music, music by Mozart, or Rap Mozart No Music no music while attempting to memorize objects pictured on a page. They were then asked to list all the objects they could Count 29 1.7 13 remember. The summary statistics for each group are shown in the table. Complete parts a and b. Mean 12.57 9.82 12.62 SD 4.15 3. 13 5.07 a) Does it appear that it is better to study while listening to Mozart than to rap music? Test an appropriate hypothesis and state your conclusion. Let group M correspond to Mozart listeners and group R correspond to rap listeners. Write the null and alternative hypotheses. Choose the correct answer below. O A. HO: HM - HR= 0 OB. HO: HM - HR = 0 HA: HM - HR 0 HA: HM - HR= 0 Test the hypothesis. t= (Round to two decimal places as needed.) P = (Round to three decimal places as needed.) State your conclusion. Use a = 0.05. evidence that the mean number of objects remembered by those who listen to Mozart is higher than the mean number of objects remembered by those who listen to rap music. Ho. There b) Create a 90% confidence interval for the mean difference in memory score between students who study to Mozart and those who listen to no music at all. Interpret your interval. The 90% confidence interval for the negative difference in means is (],). (Round to three decimal places as needed.)