Ответ:

1. 4 \(\cdot\) 3 \(\cdot\) \(\sqrt{5}\) \(\cdot\) \(\sqrt{3}\) \(\cdot\) \(\sqrt{3 \cdot 5}\) = 12 \(\cdot\) \(\sqrt{5}\) \(\cdot\) \(\sqrt{3}\) \(\cdot\) \(\sqrt{3}\) \(\cdot\) \(\sqrt{5}\).
2. 12 \(\cdot\) \(\sqrt{5} \cdot \sqrt{5}\) \(\cdot\) \(\sqrt{3} \cdot \sqrt{3}\) = 12 \(\cdot\) 5 \(\cdot\) 3.
3. \(\text{Ответ: }\) 180.