4) A census of residents of a small town with a population of 2,000 revealed that the mean age of the town's residents (i.e. ) is 45.51 years old with a standard deviation of 18.04. From this population, research team 1 pulls 20 random samples of 20 residents, and research team 2 pulls 20 random samples of 100 residents. Each research team computes the mean and standard deviation for every sample of residents it draws. The computations are provided below. As we discussed, the purpose of pulling the samples is to generate the sampling distribution of sample means. Although recreating the sampling distribution for the two sample sizes requires the research teams to pull all possible combinations of 20 residents in the first case and all combinations of 100 in the second, assume here that 20 random samples are sufficient to recreate the entire sampling distribution. a) Given what the researchers know, why is it unnecessary for them to use random sampling to estimate the mean age of the town's residents