Resolved: Array.sort() on multiple properties

Question:

I have an array, productData with multiple properties. This is how I currently sort the array by monthlyCost, ascending.
How can I modify this to sort all items by a boolean property isPromoted, followed by monthlyCost?
My array should start with all items where isPromoted == true sorted by monthlyCost, then all items where isPromoted == false sorted by monthlyCost.
The unary plus is optional in plain JavaScript, but in a TypeScript context, you’ll need to be explicit about the conversion to number and apply +.

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