The Cambridge Power and Light Company selected 20 residential customers at random. Following are the amounts, to the nearest dollar, the customers were charged for electrical service last month:

The Cambridge Power and Light Company selected 20 residential customers at random. Following are the amounts, to the nearest dollar, the customers were charged for electrical service last month: $76 29 75 128 50 65 54 33 25 100 42 117 25 73 109 170 172 30 66 161 a. Compute the arithmetic mean. (Round the final answer to 2 decimal places.) Arithmetic mean b. Indicate whether it is a Statistic or a Parameter. (Click to select) v (Click to select) Statistic Parameter