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1.
3 20 . 3 15 .
: 3 3 = 9 , 15
R = U / I
U = U N * U
U = 15
U = 3
I = 20 = 0.02
R = (15-3*3)/0.02 = 300 = 0.3
2.
3 20 . 4 7
: 4 3 = 12 , , -. 2 . . .
R = U/I
U = U N * U
U = 7
U = 3
I = 20 = 0.02
R = (7-2*3)/0.02 = 50 = 0.05
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