Dima) 4. 8 пФ b) 23. 8 пФ
C1=10 пФ, C2=20 пФ, C3=30 пФ,C4=40 пФ
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a) 1/C=1/C1+1/C2+1/C3+1/C4=1/10+1/20+1/30+1/40
C=4. 8 пФ
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b) C=C1*C2/(C1+C2) + C3*C4/(C3+C4)=10*20/(10+20) + 30*40/(30+40)=23. 8 пФ
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Kraus