# How to correctly use FormulaData

I am exploring some of the functions involving units and formulas, and wondered how to input quantities if the variable has a subscript.

This works

FormulaData["NewtonsLawOfUniversalGravitation",
{"r" -> Quantity[12, "Meters"],
QuantityVariable[Subscript["m", 1], "Mass"] ->
Quantity[12, "Kilograms"],
QuantityVariable[Subscript["m", 2], "Mass"] ->
Quantity[12, "Kilograms"]
}
]


But when I tried to evaluate using a subscripted m, it doesn't recognize the variable.

I checked the documentation and didn't see any examples with subscripted variables.

Any help with the proper way to work with these kinds of expressions would be appreciated.

formula = FormulaData["NewtonsLawOfUniversalGravitation"];