Two overlapping triangles are to be rendered in screen-space. One of the triangles is untextured but coloured, the other is textured. Either one of the triangles could be semi-transparent. a) Describe how the transparency value is stored and calculated for each fragment of: i) The untextured coloured triangle [8 marks] ii) The textured triangle [10 marks] b) How and where is the transparency value of the fragment of the triangle used to calculate the final colour of the fragment in the screen buffer? [12 marks]