Question 5. [9 marks] [Chapter 6] (a) (b) In 2010, PopCap Games commissioned a survey of adult mobile phone gamers in the United States and in the United Kingdom. A similar survey was also carried out in 2009. Some of the information from the survey is given below: Do you play mobile phone games for less than 60 minutes per week? 2009: Yes (521) Total {559) 2010: Yes (554) Total (314) How often do you typically play on your mobile phone? 2009 Daily 36 2-3 times per week 1 19 once a week 59 2-3 times a month T2 once a month or less 323 Total 659 2010 234 296 103 33 43 314 454 of the gamers surveyed in 2010 had recommended games to others. This group was asked what inuenced them to recommend a game. They could choose as many answers as they wished. The answers, with the percentages, selecting them were: 33% From a trusted brand 33% Controls simple to use 49% Easy to learn 36% Fun to play 40% Good value 36% Great graphics and sound 45% Is challenging 41% Lots of levelsfmodes State the sampling situation (a, b or c) for calculating the standard error of the difference in the following scenarios: (i) estimating the difference between the proportion of gamers that played less than 60 minutes per week in 2010 and the proportion of gamers that played once a month or less in 2010. (ii) estimating the difference between the proportion of gamers that played daily in 2009 and the proportion of gamers that played daily in 2010. (iii) estimating the difference between the proportion of gamers that played daily in 2010 and the proportion of gamers that had recommended games to others in 2010. [3 Marks] For gamers who recommended games to others in 2010, calculate a 95% condence interval for the difference between the proportion of gamers who would recormnend a game because it is flm to play and the proportion of gamers who would recommend a game because it is challenging. Interpret your results. [6 Marks] Note: You must clearly show that you have followed the \"step-by-step guide to producing a condence interval by hand\" given in the Lecture Workbook, Chapter 6. Use the rprocedures tool to nd values for t-multipliers and standard errors