B & C
Step-by-step explanation:
2:9 can also be written as 2/9
A. 9:2 is just the reciprocal of 2:9 so it is not equivalent to it
B. 18:81 is 2Γ9:9Γ9 meaning that is equivalent to 2:9
C: 12:54 is 2Γ6: 9Γ6 so it is equivalent to 2:9
Since the two correct answers have already been found, I don't need to explain more.
Hope this helped!!!
8000 is your answer
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