<p>The nucleus and an atom can be assumed to be spherical. The radius of the nucleus of mass no. A is given by&nbsp;<math xmlns="http://www.w3.org/1998/Math/MathML"><mn>1</mn><mo>.</mo><mn>25</mn><mo>&#160;</mo><mo>&#215;</mo><mo>&#160;</mo><msup><mn>10</mn><mrow><mo>-</mo><mn>13</mn></mrow></msup><mo>&#160;</mo><mo>&#215;</mo><mo>&#160;</mo><msup><mi>A</mi><mrow><mn>1</mn><mo>/</mo><mn>3</mn></mrow></msup></math>&nbsp;cm. The atomic radius of atom is 1 A. If the mass no. is 64, the fraction of the atomic volume that is occupied by nucleus is:</p>