A Ltd owns a quarry. It extracts stone from this quarry and sells it to B Ltd for £10,000 plus VAT. B Ltd converts all of the stone into paving slabs and sell s these slabs to C Ltd for £18,000, plus VAT. C Ltd owns a garden centre, where the paving slabs are sold to the general public for a total of £32,000, plus VAT. Show how VAT is charged and collected at each stage of this process, assuming that VAT is to be calculated at 20% throughout.