I think the answer is C because there isn't really a pattern, it's increasing then decreasing then increasing and decreasing and so on. So if you do find a pattern then it wouldn't be C for sure, but since there is no pattern I'm going for C. Hope that's right. .-.
To figure this out i would just dived 2.8 by 3 then multiply by two. I do not know if you must keep it as a fraction but this is the easiest way for me to do it