1 It is suggested that the English results at Valley High School have been improving in the last five years. Choose a suitable sampling method to collect data that might be used to give evidence as to whether this is true or not. Collect the sample and save it for use in sections 2.2 and 2.3. 2 A dog kennel has 120 dogs. The ages of the dogs, in order, are shown below. 1. 1, 1, 1, 1, 1, 1. 1, 1, 1, 2, 2, 2. 2. 2. 2, 2, 2, 3, 3, 3. 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 6, 6, 6, 6, 6, 6, 6, 6, 6, 7, 7. 7, 7, 7. 7, 7, 7. 7, 7, 8, 8, 8, 8. 8. 8, 8, 8, 8. 9. 9, 9. 9, 9, 10, 10, 10, 10, 11, 11, 11, 11, 12, 12, 12, 13, 13, 13, 14, 14, 15, 16, 16. a Construct a table of values to represent the ages of the dogs and the frequency of their ages. b A sample of the population was taken to check the health of the dogs in the kennel. A systematic sample of every 5 dogs was used. How many dogs were taken for the sample? c In order to take a sample of 50 dogs, stratified by their age, state the number of dogs of each age you need to select. 3 In a poll to predict the results in an election, a sample from the population is taken with the intention of providing an accurate forecast. Explain why the sample would be stratified, and suggest different strata that might be important.