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Find the central angle using a ratio in regards to angle and circumference.
The radius is 27 units, so use the following equation to calculate circumference:
C = 2rπ
Therefore:
C = 2(27)π = 54π
Since we have the total circumference, we can write the following proportion:

Cross multiply:
54πx = 6480π
Divide both sides by 54π to isolate for x:
x = 120°
Answer:
as shown in the attached file.
Step-by-step explanation:
The detailed, step by step explanation and application of integral with appropriate substitution to get the expression for the time of extinction is as shown in the attachment.
Answer:
((1)/(2),-(1)/(2))
Step-by-step explanation: