Taking into consideration the figure:

Size the reticular structure linking the tanks to the central body of the spacecraft.

Calculate the MOS assuming the FOS$=2.$

Evaluate the structural mass.

Considering the following data:

$m_s=130kg$

$n=5$

$E_{Al}=70$GPa

${}_{\text{y}\text{A}\text{l}}=250$MPa

${}_{Al}=2700k\frac{g}{m^3}$

$L=30cm$