20. Simplify the expression: \(4 \cdot \frac{3}{5}y \cdot 2z\)

To simplify the expression \(4 \cdot \frac{3}{5}y \cdot 2z\), we multiply the numerical coefficients and the variables separately.

Multiply the coefficients: \(4 \cdot \frac{3}{5} \cdot 2 = 8 \cdot \frac{3}{5} = \frac{24}{5}\).

Multiply the variables: \(y \cdot z = yz\).

Combine the results: \(\frac{24}{5}yz\).

Ответ: \(\frac{24}{5}yz\)