- The expression for price \( p \) in terms of demand \( x \) is \( p = 300 - \frac{x}{10} \) with domain \( 0 \leq x \leq 3000 \).
- The revenue function is \( R(x) = 300x - \frac{x^2}{10} \) with domain \( 0 \leq x \leq 3000 \).
- The marginal revenue at a production level of 1600 clock radios is \( R'(1600) = -20 \).
\[
\boxed{p = 300 - \frac{x}{10}}, \quad \boxed{R(x) = 300x - \frac{x^2}{10}}, \quad \boxed{R'(1600) = -20}
\]