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.
The answer is -1.5. Hope this helps
For 6 hours charges $330
for 9 hours charges x
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x = 9*330/6 = 495 so choice C. is right
a^2 - b^2 = (a + b)(a - b)
In this case
49x^4y^2 - 4z^2
= (7x^2y)^2 - (2z)^2
= (7x^2y + 2z)(7x^2y - 2z)
Factors are (7x^2y + 2z) and (7x^2y - 2z)
Answer:
D) 7x^2y + 2z