= Solution
The original PDF calls $\epsilon_r$ a relative <magnetic permeability> while also specifying a nonmagnetic <dielectric>. These descriptions are inconsistent if read literally. The physically consistent interpretation of the notation is <relative permittivity> $\epsilon_r=2$ and relative <magnetic permeability> $\mu_r=1$.
Let $a=3\,\mathrm{mm}$ and let $b=6\,\mathrm{mm}$ be the inner radius of the outer conductor. For line charge density $\lambda$, <Gauss's law> gives $E_r=\lambda/(2\pi\epsilon r)$, hence
$$
V=\int_a^b E_r\,dr=\frac{\lambda}{2\pi\epsilon}\ln\frac ba,
\qquad C'=\frac\lambda V=\frac{2\pi\epsilon_0\epsilon_r}{\ln(b/a)}.
$$
The <magnetic field> in the <dielectric> is $H_\varphi=I/(2\pi r)$. Its <energy> per unit length gives
$$
\frac12L'I^2=\int_a^b\frac{\mu H_\varphi^2}{2}\,2\pi r\,dr,
\qquad L'=\frac{\mu_0\mu_r}{2\pi}\ln\frac ba.
$$
Using $b/a=2$,
$$
\boxed{C'=1.61\times10^{-10}\,\mathrm{F\,m^{-1}}=161\,\mathrm{pF\,m^{-1}},}
$$
$$
\boxed{L'=1.39\times10^{-7}\,\mathrm{H\,m^{-1}}=139\,\mathrm{nH\,m^{-1}}.}
$$
These are the <lossless coaxial line parameters>, assuming negligible field penetration into the conductors. If the quoted radii instead referred to an outer diameter or if $\mu_r=2$ were intended, the data would need clarification; the stated <dielectric> and nonmagnetic assumptions support the interpretation above.
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