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.
C I think not sure I think tho.
18 that question is confusing so I guessed sorry dude
We start with the more complicated side which is the left side, and show that, on using some trigonometric identities, we will get the term on the right side .

Using Quotient identity for tangent function, we will get


Taking out sine function from the numerator

Cancelling the common term of numerator and denominator
