(i) How do point estimators and interval estimators differ? (ii) The mean and median score in a Statistics exam is 70 and 73, respectively. Due to the high level of difficulty of the exam, the lecturer decides to give 5 bonus points to every student. What will be the new mean and median scores? Provide a brief explanation. (iii) A sample of shoppers at the Westfield shopping centre at Garden City in Brisbane was asked the following questions. Identify the type of data each question would produce. a. What is your age? b. How much did you spend? c. What is your marital status? d. Rate the availability of parking: excellent, good, fair or poor (iv) List four important points to consider when designing a questionnaire. (v) The weather bureau records the daily rainfall in Darwin. Can the variance in rainfall be negative? Why?