Hey there!
To figure out what "x" means, you can divide the numbers 126 and 14 . . .
126 divided by 14 = 9
9 x 14 = 126
9 = x
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x = 9
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Hope this helps you.
Have a great day!
I know for a fact B is wrong, so you can mark that off. I got C.
Answer:
2.4 hours
Step-by-step explanation:

2.4 hours
You can make 5 prisms and one extra unit left