A student wants to investigate the hypothesis: 'Pupils in Year 11 spend more time on homework each week than pupils in Year 7.' She plans to sample 20 pupils from each year group.
(a)Plan: State a suitable sampling frame the student could use to select pupils for this investigation, and give one advantage of using it.(2)
(b)Collect: Design a suitable data collection sheet to record, for each pupil sampled, their year group and the number of hours they spend on homework in a week, to the nearest hour.(3)
(c)Process: State one calculation the student could carry out on the results for each year group, so she can compare the average time spent on homework.(1)
(d)Interpret: Give one reason why the student should be cautious about generalising her conclusion to all pupils nationally.(1)
(Total for Question 14 is 7 marks)