Answer to Question 1
Open-throated singing
Use of call-and-response
Eskanye songs typically have two melodic phrases (A and B), and the form may be described as a kind of incomplete repetition.' The resulting form is: AAB AB.
The use of vocables
The phrase gai na we yo he ya is used to end both phrases of this song and is used to mark the endings of virtually all Eskanye songs. (Worlds of Music, citing Diamond 2008:107.)
These songs are performed at a gathering called a Sing which is a large community event that is held in a longhouse.
Answer to Question 2
It is sung to the accompaniment of the how horn rattle and the water drum.