Consider a 2 nm spherical silver nanoparticle. a. How many silver atoms are on the surface (include calculation of the atomic radius)? b. What % of the total number of atoms are on the surface? c. Plot the specific surface area and the % atoms on the surface as a function of sphere radius for 0.1 nm < R < 100 nm. Show any equation you used to calculate the values for the plot. What is the physical limit of this calculation?