I'm trying to solve this , but my computer gives no results ...

NSolve is not able to solve this system?..

Thanks

ClearAll["Global`*"];
t1 = Quantity[750 + 273, "Kelvin"]
t2 = Quantity[1000 + 273, "Kelvin"];
t3 = Quantity[1250 + 273, "Kelvin"]
[Rho]1 = Quantity[5.50 , "grams/cu Centimeter"]
[Rho]2 = Quantity[5.44 , "grams/cu Centimeter"];
[Rho]3 = Quantity[5.37, "grams/cu Centimeter"]
ns1 = Quantity[9.21 10^19 , "Meter^-3"]
ns3 = Quantity[5 10^22, "Meter^-3"]
Subscript[A, O] = Quantity[16, "grams/Mole"]
navogadro = Quantity[6.022 10^23 , "Mole^-1"]
k = Quantity[8.6173324 10^-5, "ElectronVolts/Kelvin"]


NSolve[{ns1 == ((navogadro [Rho]1 )/(
     Subscript[A, M ] + Subscript[A, O])) Exp[-(Qs/(2 k t1))], 
  ns3 == ((navogadro [Rho]3 )/(
     Subscript[A, M ] + Subscript[A, O])) Exp[-(Qs/(
      2 k t3))]}, {Subscript[A, M], Qs}]