When Wires Turn Useless

I guess I will never fall short of useless wire. This time I had a wire with a total resistance of $$15 \Omega$$ and then I cut it into 30 equal pieces to form a regular Icosahedron as shown below. Then what is the equivalent resistance between any two opposite nodes in $$\Omega$$?

If the equivalent resistance between any two opposite nodes is $$R$$, then enter the value of $$100R$$.

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