Algebra-1

Question Analysis
This question tests the student's ability to apply the explicit formula for the nth term of a geometric sequence, specifically with a negative common ratio.

Key Concept Explanation
The explicit formula for the nth term of a geometric sequence is given by (). Here, is the first term, is the common ratio, and is the term number.

Step-by-step Solution
1. Identify the given values: , , and .
2. Substitute these values into the explicit formula: