Consider the Following Counting Problem

question 18

Multiple Choice

Consider the following counting problem. How many different sequences of 3 letters can be formed using the letters a, b, c, d, e if repetition is allowed?
To solve this problem which of the following rules would you use?

• A)The basic counting rule only
• B)The combinations rule only
• C)Both the permutations rule and the basic counting rule
• D)The permutations rule only

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Pollution

The contamination of the environment by substances that are harmful to living organisms and natural resources.

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Relationship between the quantity of a good that producers are willing to sell and the price of the good.