(a) What amount has his department spent on overseas travel for (i) the Deputy Minister, (ii) the Director-General and (iii) the Deputy Director-Generals in the period 1 May 2014 until 1 September 2015, (b) what was the purpose of each specified visit in each case, (c) what were the destinations and (d) what amount was spent on (i) flights, (ii) accommodation and (iii) daily allowances?