is this a calculation or sig fig error I'm making?

0/1 point (graded) Two metal sheets, one made of an isotope of Sc with a nuclear radius of 3.54fm and one made of an isotope of In with a nuclear radius of 4.61fm, were left unlabeled. Both sheets look identically thin and have an area of 1.50102m2. You have been tasked to use a backscattering experiment to differentiate between the two sheets. You decided to bombard each sheet with 5.001010 alpha particles. Assuming that there are 5.001021 atoms in each sheet, how many backscattered alpha particles would you observe from the Sc metal sheet? particles x 2.051032 Your answer is outside the acceptable bounds. You may have made a calculation or rounding error