so; (2.5)*(7) * 10⁽⁻¹⁶⁾ = 17.5 * 10⁻¹⁶ _______________________________________________ SInce the answer choices are given in scientific notation; in terms of "1.75"; we rewrite this value in such format to get the equivalent value; by dividing by "10" ; to get: "1.75 * 10⁻¹⁵ " (note: this value is equivalent; since the number of "zeros" is adjusted. _______________________________________________ The answer is: [B]: " 1.75 * 10⁻¹⁵ " . _______________________________________________