§ Задание 447
\[\boxed{\text{447\ (447).}\text{\ }\text{Еуроки\ -\ ДЗ\ без\ мороки}}\]



\[\left\{ 1 \right\}\ \subset \left\{ 1,\ 2 \right\};\]
\[\left\{ 2 \right\}\ \subset \left\{ 1,\ 2 \right\};\]
\[\varnothing \subset \left\{ 1,\ 2 \right\};\]
\[\left\{ 1,2 \right\} \subset \left\{ 1,\ 2 \right\}.\]

