Respostas

2013-09-14T20:02:50-03:00
2cm² = 25.10^-6 * A * 10
2 = 250.10^-6 * A
A = 250.10^-6 / 2
A = 125.10^-6
A = 1,2.10^-4 cm 
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2013-09-14T22:54:27-03:00
2=A . 25.10^-6  . 10
2= 250.10^-6 A
A= 2/ 250.10^-6
A= 0,008.10^6
A=8.10^3 cm² ou A= 8000 cm²
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