Question 1 (6 points) e 2: [6 marks] An epidemiologist wanted to investigate whether the mRNA vaccine was effective against the emerging delta variant of COVID-19 virus. In particular, the epidemiologist wanted to find out if there was a relationship between mRNA dosage (no dose, single dose, two doses) and being infected with the delta variant. A simple random sample of 500 Canadians was selected to study this. The results are summarized in the following table. e 3: Infected with MRNA vaccine dose COVID-19 delta variant No dose Single dose Two doses Total Yes 32 100 11 143 e 4: No 10 225 122 537 Total 42 325 133 500 a) [2 marks] Calculate the expected frequency of the cell "No and no dose" and provide an interpretation of its value in the context of the problem. ge 5: b) [4 marks] The chi-square statistic is 74.2. Can the researcher conclude that being infected with the delta variant is independent to mRNA vaccine does? Clearly show the steps of hypothesis testing and use an appropriate decision point value to support your conclusion