The moisture content in a solid waste was found to be 12%. If the ash content is 6% and the energy content of the solid waste on the discarded basis is 18000 kJ/kg, then energy content on the dry basis and on an ash-free dry basis, respectively are:
1
20456 kJ/kg & 32556 kJ/kg
2
20456 kJ/kg & 21952 kJ/kg
3
32556 kJ/kg & 20456 kJ/kg
4
32556 kJ/kg & 21952 kJ/kg