解：圓錐的側(cè)面積?$S_{錐側(cè)}=\frac {1}{2}×4\pi ×2.5 = 5\pi (\mathrm {m^2})。$?
圓柱的側(cè)面積?$S_{柱側(cè)}=3×4\pi = 12\pi (\mathrm {m^2})。$?
?$ $?鐵皮的面積?$S = 2×(S_{錐側(cè)}+S_{柱側(cè)})=2×(5\pi + 12\pi )=34\pi 。$??$ $?
把?$\pi ≈3.14$?代入，?$S≈34×3.14 = 106.76≈106.8(\mathrm {m^2})。$?
