R12 = (R1*R2) / (R1+R2)
R123 = (R1*R2) / (R1+R2) +R3
1/R = 1/R123 +1/R4
R= (R123*R4) /(R123+R4) = ((R1*R2) / (R1+R2) +R3) * R4 / ((R1*R2) / (R1+R2) +R3 +R4)
дальше арифметика - подставь цифры
F=m*g =3.5*9,8= 34,3H
F=m*g= 0.4*9.8=3.92H
F=m*g=1500*9.8=14700H
F=m*g=0.06*9.8=0.588H
F=P=m*g=5.3*9.8=51.94H
m=P/g=700/9.8≈71.428кг
1800сек/60=30мин
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