Answer:
24.
Step-by-step explanation:
We can use the factorial function to find the number of unique arrangements in a word.
There are 4 unique characters in 'OPAL'. As such, 4! = 24.
In the case that there were repeating characters, such as 'OPALA', then we would divide by the factorial of the number of repeating letters. That looks something like this:

Hope this helped.
Number of ribbons that can be cut = 6 ÷ 1/2
Number of ribbons that can be cut = 6 x 2/1
Number of ribbons that can be cut = 12
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Answer: 12 1/2 foot pieces can be cut from 6 feet ribbon
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Answer:
A (4,6)
ok im going to go through this step by step
4(4)=3(6)-2
16=18-2
16=16 (true solution)
18=3(4)+(6)
18=12+6
18=18 (true solution)
X is always dependant to Y. so that should answer the 1st one. the 2nd looks to be around 17-18. 17.5 maybe. and the 3rd is yes cause he does not go to the pool so it isnt any cost.