\[\boxed{\mathbf{2}\mathbf{.}}\]
\[1)\ 10,\ 20,\ 30,\ 40,\ 50,\ 60,\ 70,\ 80,\ \]
\[90,\ 100.\]
\[2)\ 100,\ 90,\ 80,\ 70,\ 60,\ 50,\ 40,\ 30,\]
\[\ 20,\ 10.\ \]