(1) What has been spent against the budgeted amounts for the maintenance of national roads on every national road in each of the past three financial years; (2) what processes, procedures and mechanisms exist to ensure that roads are maintained to be always at an optimal level for use; (3) whether any backlog exists in this regard; if not, what is the position in this regard; if so, (a) for which road, (b) what is the nature of the maintenance backlog and (c) what amount of money is required to perform such maintenance in each case?