A laterally insulated bar of length $10 \mathrm{cm}$ and constant cross-sectional area $1 \mathrm{cm}^{2}$, of density $10.6 \mathrm{gm} / \mathrm{cm}^{3}$, thermal conductivity $1.04 \mathrm{cal} / \mathrm{cm}$ sec $^{\circ} \mathrm{C}$, and specific heat conductor $)$ has initial temperature $f(x)$ and is kept at $0^{\circ} \mathrm{C}$ at the ends $x=0$ and $x=10$, Find the temperature $u(x, t)$ at later times, Here, $f(x)$ equals:
$$f(x)=1-0.2|x-5|$$