a . The Consumer Price Index ( CPI ) is an index that measures changes in the average prices fo consumer goods and services . Explain why CPI is not a perfect measure of inflation . b . Suppose the Australian Bureau of Statistics in 2021 reported as follows : The Armed forces , children below 15 years, the disabled and retired population were 12.2 million of the Australian population Total population : 26.6 million Adult Australians employed : 13.6 million Based on this information , answer the questions below i . Calculate Australia's labour force in 2021 ii . Calculate Australia's unemployment rate in 2021