Answer: 314.16
Step-by-step explanation: To find the area of a circle you have to square the radius then multiply by pi. 10 squared is 100 then multiplied by pi is 314.16 (rounded to the nearest hundredth).
80 copies --> 5 minutes
8 * 80 copies --> 8 * 5 minutes
640 copies --> 40 minutes
Answer: 640 copies
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