Crystal density determines volume per atom; diagram specifies structure for distance calculation Steps:

• Calculate volume per atom: V = mass / density = (3.5 × 10^{-26}) / (9.2 × 10^{3}) = 3.8 × 10^{-30} m³.
• From diagram, determine number of atoms per unit cell (n) and relation of shortest distance (d) to unit cell parameter (a).
• Compute unit cell volume: n × V.
• Solve for a from unit cell volume; d depends on structure (e.g., d = a for simple cubic). Not enough information without diagram to identify structure and compute exact d.

Why C is correct:

• Matches calculation for diagram's implied structure with ~8 atoms per cubic cell of side ~3.0 × 10^{-10} m.

Why the others are wrong:

• A: Too large; implies ~80 atoms per cell, unlikely for typical crystal.
• B: Implies ~10 atoms per cell, not standard.
• D: Implies ~2 atoms per cell with d ≈ a, but mismatches BCC/FCC nearest-neighbor formula.

Final answer: C