\[\boxed{\text{81.}}\]
\[2\ 539\]
\[6\ 370\]
\[720\ 536\]
\[50\ 908\]
\[672\ 137\]
\[\boxed{\text{82.}}\]
\[3\ 503\]
\[132\ 560\]
\[78\ 742\]
\[60\ 921\]
\[6\ 237\]
\[305\ 043\]
\[\boxed{\text{83.}}\]
\[Четные\ числа:\]
\[20,\ 42,\ 84,\ 96,\ 402,\ 482,\ 540,\ \]
\[638,\ 900,\ 1000.\ \ \]
\[Нечетные\ числа:\]
\[7,\ 11,\ 395,\ 411,\ 701,\ 705,\ 799,\ \]
\[973,\ 999.\ \]