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- $ I\\\left( {1; - 1;1} \\\right)$, $ R = \\\sqrt 2$ .
- $ I\\\left( {2; - 2;2} \\\right)$, $ R = \\\sqrt {11}$ .
- $ I\\\left( { - 2;2; - 2} \\\right)$, $ R = \\\sqrt {13}$ .
- $ I\\\left( {1; - 1;1} \\\right)$, $ R = 2$.