56. All the six faces of a cube are coloured with six different colours - black, brown, green, red, white and blue according to the following instruction
1. Red face is opposite to the black face.
2. Green face is between red and black faces.
3. Blue face is adjacent to white face.
4. Brown face is adjacent to blue face.
5. Red face is in the bottom.
The upper face of the cube will be painted in which of the following color