The sentence that demonstrates correct subject-verb agreement is
<u>Dave Wiens</u>, a Denver native and champion mountain biker,<u> helped</u> design the Olympic mountain bike course in Atlanta, Georgia.
In this sentence : Exploring international mountain passes, such as those in New Zealand, Canada, and Japan, are one of the biker’s favorite hobbies. The correct verb that shows agreement would be is
Cause they dont need to if u ask me
The mood (or tone) of the prologue is considered as sombre, dark, macabre... since from the start we're being told that this story is going to be a story of love, death and loss.