Arithmetic sequences have a common difference between consecutive terms.
Geometric sequences have a common ratio between consecutive terms.
Let's compute the differences and ratios between consecutive terms:
Differences:

Ratios:

So, as you can see, the differences between consecutive terms are constant, whereas ratios vary.
So, this is an arithmetic sequence.
0.12 can be written as 12/100 or 3/25. It is very much a rational number as no square root is involved in the fractional form of the number.
Answer:
The second one or B- "He did not find the prime factors of 4."
Step-by-step explanation:
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