How many cesium atoms are needed to line up with one another to form a square grid on a 1.00 mm by 1.00 mm square surface if the diameter of a cesium atom is 0.267 nm?

• A. 2.67x10^-16 atoms
• B. 2.67x10⁷ atoms
• C. 1.40x10¹³ atoms
• D. 3.75x10⁷ atoms

Answer: (C)