Respuesta :

Answer:

125

Step-by-step explanation:

R = 4 cm , r = 2 cm

weight = 9.42 kg --> 9420 g

density = 6 g/cm³

9420g/volume cm³ = 6 g/cm³

9420/6 = volume

1570 = volume

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volume of a rod = 1570 cm³

πr²h = 1570

3.14×2×2×h = 1570

12.56×h = 1570

h = 125 cm

; length of the rod is 125 cm