Answer
The sequence is neither geometric nor arithmetic.
Work Step by Step
In order to determine if the sequence is geometric, the quotient of all consecutive terms must be constant.
Here, we have: $\dfrac{c_{2}}{c_1}=\dfrac{12}{6}$ and $\dfrac{c_{3}}{c_2}=\dfrac{36}{12}=3$
This shows that the quotient of all consecutive terms is not constant. Thus, this is not a geometric sequence.
In order to determine if the sequence is arithmetic, the difference of all consecutive terms must be constant.
Here, we have: $c_2-c_1=12-6=6$ and $c_3-c_2=36-12=24$
This shows that the difference of all consecutive terms is not constant. Thus, this is not an arithmetic sequence.
Hence, the sequence is neither geometric nor arithmetic.
