\[\boxed{\mathbf{248}.}\]
\[1)\ a = 2^{2002} + 3^{2002}\]
\[2^{1} = 2;\]
\[2^{2} = 4;\]
\[2^{3} = 8;\]
\[2^{4} = 16 = 11 + 5\]
\[2^{5} = 32 = 2 \cdot 11 + 10\]
\[2^{6} = 64 = 5 \cdot 11 + 9\]
\[2^{7} = 128 = 11 \cdot 11 + 7\]
\[2^{8} = 256 = 23 \cdot 11 + 3\]
\[2^{9} = 512 = 45 \cdot 11 + 6\]
\[2^{10} = 1024 = 93 \cdot 11 + 1\]
\[2^{11} = 2048 =\]
\[= 186 \cdot 11 + 2\ \rightarrow повтор.\]
\[2002\ :10 =\]
\[= 200\ (ост.\ 2) \rightarrow 2^{2} =\]
\[= 4\ (последняя\ цифра).\]
\[3^{1} = 3\]
\[3^{2} = 9\]
\[3^{3} = 27 = 2 \cdot 11 + 5\]
\[3^{4} = 81 = 7 \cdot 11 + 4\]
\[3^{5} = 243 = 22 \cdot 11 + 1\]
\[3^{6} = 729 =\]
\[= 66 \cdot 11 + 3\ (повтор).\]
\[2002\ :5 = 400\ (ост.\ 2) \rightarrow 3^{2} =\]
\[= 9\ (последняя\ цифра).\]
\[Последняя\ цифра\ выражения:\]
\[2^{2} + 3^{2} = 4 + 9 = 13 = 11 + 2.\]
\[Ответ:остаток\ 2.\]
\[2)\ a = 3^{2002} + 7^{2002}\]
\[Из\ пункта\ 1:\]
\[остаток\ от\ деления\ 3^{2002}\ на\ \]
\[11\ равен\ 9.\]
\[7^{1} = 7;\]
\[7^{2} = 49 = 4 \cdot 11 + 5;\]
\[7^{3} = 343 = 31 \cdot 11 + 2;\]
\[7^{4} = 2401 = 218 \cdot 11 + 3;\]
\[7^{5} = 16\ 807 = 1527 \cdot 11 + 10;\]
\[7^{6} = 5\ 764\ 801 =\]
\[= 524\ 072 \cdot 11 + 9;\]
\[\ldots\ldots\ldots\ldots\ldots\ldots\ldots.\]
\[7^{12} = 13\ 841\ 287\ 201 =\]
\[= 1\ 258\ 298\ 836 \cdot 11 +\]
\[+ 5\ (повтор).\]
\[2002\ :10 = 200\ (ост.\ 2) \rightarrow 7^{2} =\]
\[= 49 = 44 \cdot 11 + 5.\]
\[Остаток\ от\ деления:\]
\[9 + 5 = 14 = 11 + 3.\]
\[Ответ:остаток\ 3.\]