Answer is C.
Law of cosines.
cos-1(-80/240)
Answer:

is equivalent to
.
This is because 
The rule is, in order to add fractions, your denominators must be equivalent. In other words, you must have the same denominator for both fractions.
<em>Now what do we do? We add!</em>

This is because 4 + 1 = 5.
Your answer is
.
I hope this helps!
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Answer:
it will take 25.2 minutes for Lin to run 21 laps
Step-by-step explanation: give crown plsplsplsplsplsplsplsplsplspls, also have a good day!