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\includegraphics[max width=\textwidth, alt={}, center]{c403a227-586d-4c1f-a392-e475234fc0a0-12_732_581_260_774} A uniform solid cone has height 1.2 m and base radius 0.5 m . A uniform object is made by drilling a cylindrical hole of radius 0.2 m through the cone along the axis of symmetry (see diagram).

1. Show that the height of the object is 0.72 m and that the volume of the cone removed by the drilling is \(0.0352 \pi \mathrm {~m} ^ { 3 }\).
   [0pt] [The volume of a cone is \(\frac { 1 } { 3 } \pi r ^ { 2 } h\).]
2. Find the distance of the centre of mass of the object from its base.
   If you use the following lined page to complete the answer(s) to any question(s), the question number(s) must be clearly shown.