The inverter $74 \; \mathrm{ALSO} 4$ has the following specifications
\[ \begin{array}{l}
\mathrm{I}_{\text {OH } \max }=-0.4 \mathrm{~mA}, \mathrm{l}_{\text {OLmax }}=8 \mathrm{~mA}, \mathrm{l}_{i H_{\max }}=20 \mathrm{~mA} \text {, } \\
\mathrm{l}_{\text {iLmax }}=-0.1 \mathrm{~mA} \text {, }
\end{array} \]
The fan-out based on the above will be
- $10$
- $20$
- $60$
- $100$