NH3 + HNO3 ---> NH4NO3
This means 1 mol of NH3 and 1 mol of HNO3 is needed to make 1 mol of NH4NO3
Molar mass of NH4NO3
N = 14.01 g/mol*2
H = 1.008 g/mol*4
O = 16.00 g/mol*3
NH4NO3 = 80.052 g/mol
15,000 kg of anything is actuall 15,000,000 grams
So, 15,000,000/80 = 187,500 mol of NH4NO3
Means you need 187,500 mol of nitric acid, as well as 187,500 mol of ammonia.
First, nitric acid:
187,500 mol/12.0 mol/L = 15,625 L of nitric acid
And for ammonia:
187,500 mol/8 mol/L = 23,422 L of aqueous ammonia