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The following table represents data collected on the monthly income of 20 residents in a rural community. Monthly Income Frequency $10,000 - $50,000 $55,000 - $95,000 3 $100,000 - $140,000 $145,000 - $185,000 $190,000 - $230,000 $235,000 - $275,000 Determine the: a) Median income (3 marks) b) Mean income (3 marks) c) Modal income (3 marks) d) Skew of the distribution (2 marks)