Feminine and masculine endings are determined by the stressed or unstressed syllables at the end of a line of poetry?

Answer 1

Correct.

At the end of each line a stressed final syllable is said to be 'a masculine ending' and an unstressed final syllable is said to be 'a feminine ending'.

Answer 2

In poetry, feminine endings occur when the final syllable of a line is unstressed, while masculine endings occur when the final syllable is stressed. This distinction can affect the rhythm and flow of a poem.