The Brazilian free-tailed bat can travel 99 miles per hour. After sunset, a colony of bats emerges from a cave and spreads out in a circular pattern. How long before these bats cover an area of 80,000 square miles? Use π = 3.14.

For a circular spread, the covered area is A = πr², where r is the distance the bats travel. Set 80,000 = 3.14r², giving r ≈ 159.6 miles; at 99 miles per hour, the time is 159.6 ÷ 99 ≈ 1.6 hours. The correct choice is 1.6 hours.

AI-written and checked against the verified answer.