At a festival, spherical balloons with a radius of 30.cm are to be inflated with hot air and released. The air at the festival will have a temperature of 25°C and must be heated to 100°C to make the balloons float. 2.00kg of propane C₃H₈ fuel are available to be burned to heat the air. Calculate the maximum number of balloons that can be inflated with hot air. 

Here are some data you may find useful: 

Specific heat capacity of air: 1.009J·g°C 

Density of air at 100°C: 0.946kgm³

Density of propane at 100°C: 1.440kgm³ 

Formation enthalpy of propane at 25°C: −103.85kJmol