5) A burglar alarm emits a signal that can be heard for 60 miles in all directions. If the intensity of the noise is strengthened so that it's audibility is increased by 40 miles in all directions, by approximately how many square miles is its region of audibility increased?

(A) 6,300
(B) 10,000
(C) 10,300
(D) 20,000
(E) 31,400

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i found the answer 6400 pi

6400x3.14= 20096 approximately 20000

(D) 20,000

((----40mil-----((------60mil-----Signal----60mil------))-----40mil------))


Pi*(100^2 - 60^2)= 3.14*(10000-3600)
=3.14*6400=20096 approximately--> 20000 :)

absolutely :)
sevgili kayamusty ve genius, elinize sağlık..