<p>A silicon specimen is made into a&nbsp;P-type semiconductor by dopping, on an average, one helium atoms per&nbsp;<math xmlns="http://www.w3.org/1998/Math/MathML"><mn>5</mn><mo>&#215;</mo><msup><mn>10</mn><mn>7</mn></msup></math>silicon atoms. If the number density of atoms in the silicon specimen is <math xmlns="http://www.w3.org/1998/Math/MathML"><mn>5</mn><mo>&#215;</mo><msup><mn>10</mn><mn>28</mn></msup></math>&nbsp;atom/m&sup3; then the number of acceptor atoms in silicon per cubic centimeter will be</p>