4)Assume that you are considering cluster sampling to estimate the average municipality tax in Sweden. Assume that you want to draw =2or 3clusters of municipalities, and investigate all municipalities in each of the randomly selected clusters in order to estimate the overall average tax rate.NOTE:You are notrequired to do any sampling or calculations;only reasoning is required!a)What basic properties should clusters have in order to justify cluster sampling?b)Which variable (of 1-5) is in your view most suitable to use for defining clusters of municipalities?Are any of the available variables useful for defining clusters?Would you recommend cluster sampling to estimate the average municipality tax in Sweden in this setting? https://docs.google.com/file/d/17ko-PmsDKwb7EpE_nH8d40v5o2m496F_/edit?usp=docslist_api&filetype=msexcel