Dave is setting out slabs of paving stonefor a patio area. He has 16 paving slabs to arrange in four rows with four in each row.
The stones are Orange,red, yellow or white with four of each colour.

Looking from the back door, the nearest row is row 1, the next, row 2 , with 4 being furthest from the house. Dave wants each row across each column and each diagonal of four to contain a slab of each colour. Row 4 will have a yellow slab far left and a white slab far right. On row 2 the second slab from the left will be red.


What colour will the slabs be on rows 1-4?