(a) What volume of water (i) was or (ii) is to be discharged from the Lesotho Highlands Water Project to mitigate the effect of water restrictions in Mangaung, (b) what (i) percentage and (ii) volume of water has been purified for use by residents of Mangaung in this regard, (c) what is the (i) cost per unit and (ii) total cost for the water to be discharged for this purpose and (d) who is responsible for the payment of these costs?