This is the 170th most frequent Polish word.
wysokości
"Height" or "altitude."
In this sentence, 'wysokości' is part of the phrase 'wysokość opłaty', meaning 'amount of the fee', which relates to a financial value or amount.
Komisja ustaliła wysokość opłaty.
The committee determined the amount of the fee.
Here, 'wysokości' refers to 'altitude', indicating the height above a specific baseline.
Samolot leciał na wysokości 10 000 metrów.
The airplane flew at an altitude of 10,000 meters.
In this context, 'wysokości' relates to 'heights', meaning the state of being at a height and indicating physical elevation.