we have that
the surface area of a truncated solid is equal to
[tex]SA=\pi\cdot\lbrack LR+Lr+R^2+r^2\rbrack[/tex]
where
L is the slant heigh --------> L=6 cm
R=8 cm
r=4 cm
substitute
[tex]SA=\pi\cdot\lbrack6\cdot8+6\cdot4+8^2+4^2\rbrack[/tex][tex]\begin{gathered} SA=\pi\cdot\lbrack48+24+64+16\rbrack \\ SA=\pi(152) \\ SA=477.52cm2 \end{gathered}[/tex]
