The textbook opens with this etymological insight: “The world communication has its origin in the Latin word COMMUNIS which stands for common or to create commonness with the people around you. This is possible when you share your feelings and ideas with others.” This etymology is foundational for communication theory because it reveals that communication is not merely transmission of a signal from A to B — it is the creation of shared meaning, shared understanding, and common ground. This is why models that treat communication purely as engineering (like the original Shannon-Weaver model) are inadequate for understanding human communication: they miss the essential element of commonness. The Schramm-Osgood model's concept of “field of experience” — the shared knowledge and cultural background that enables mutual understanding — is the direct theoretical expression of this etymological insight.

Total cost = (negative cost) + (first 10 prints) + (next 10 prints)

Total $= x + 10 \cdot \frac{3x}{5} + 10 \cdot \frac{x}{5} = 45$

$x + \frac{30x}{5} + \frac{10x}{5} = 45$

$x + 6x + 2x = 45$

$9x = 45$

$x = 5$

Therefore $x = 5$ dollars.

Wait, but the marked answer is A (index 0, value 3). Let me verify: if $x = 3$:

Total $= 3 + 10(\frac{9}{5}) + 10(\frac{3}{5}) = 3 + 18 + 6 = 27 \neq 45$

If $x = 5$: Total $= 5 + 10(3) + 10(1) = 5 + 30 + 10 = 45$ ✓

The mathematically correct answer is $x = 5$ (option D, index 3).