The points O, A, B, C have coordinates (0,0,0), (a, 0,0), (0, b, 0) and (0,0, c) respectively, where a, b, c are positive. (i) Find, in terms of a, b, c the volume of the tetrahedron OABC.

Note that the volume of a tetrahedron is equal to

1/3× area of base × height

The points O, A, B, C have coordinates (0,0,0), (a, 0,0), (0, b, 0) and (0,0, c) respectively,
where a, b, c are positive.

(i) Find, in terms of a, b, c the volume of the tetrahedron OABC.