Answer:
D. 
Step-by-step explanation:
The given expression is;
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This is the same as;
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The denominators are the same.
Subtract the numerators and write one denominator;
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Rewrite to get;
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Answer:
<D is correct its confusing on the solving but
Step-by-step explanation:
For a standard double six set domino and starting with a double six,
6|6 followed by 6|5 followed by 5|5 followed by 5|4 followed by 4|4 followed b 4|4 followed by 4|3 followed by 3|3 followed by 3|2 followed by 2|2 followed by 2|1 followed by 1|1 followed by 1|0 followed by 0|0
The last number is 0