Final answer:
To find the average change in temperature each day, divide the total decrease of 6 degrees by the 3 days, which results in an average daily decrease of -2 degrees.
Step-by-step explanation:
The question is asking for the average change in temperature each day over a period of three days, given that the temperature dropped by a total of 6 degrees. To solve for the average daily change, we can divide the total change in temperature by the number of days. Mathematically, this would be -6° (total drop in temperature) divided by 3 days, resulting in an average change of -2° per day. Therefore, the correct answer is c) -2 degrees.