A. (6/4, -8/9,33/9)

B. (16/9, 20/9, 33/9)

C. (16/4,38/9, 13/9)

D. (0,2,3)

The circumradius of the triangle formed by the points (2,-1,1) , (1,-3,-5), (3,-4,-4) is

The orthocentre of the triangle formed by the points(2,-1,1), (1,-3,-5), (3,-4,-4) is

The points of trisection of the line segment joining (2,-3,5), (3,1,-2) are

If the origin is the centroid of the tetrahedron for which (2,-1,3), (-1,3,1), (3,4,-2) are three vertices then the fourth vertex is

The locus of a point which is at a distance of 5 unit from (2,1,-3) is