Which act does tris believe is a braver act than going down the zip line?

Tris and the others are zip lining from the Hancock Tower until Lake Shore Drive and when it is her turn she describes that they are grasping each other's arms to form a net beneath her and that in order to get down she has to trust them and that at that point they are hers and she is theirs. This is what she considers a braver act than sliding down the zip line.

moon-letters were a method of writing invented by the dwarves. moon-letters were ordinary runes, but written in such a way that they could only be read when the light of the moon shone behind the writing. some moon-letters could be read by any moonlight, but it was possible to make the writing even more secret. more sophisticated moon-letters could only be read by the light of the same shape of moon, or at the same time of year, as when they were written. hope this !

1. c- the tunnel project was worthwhile.

2. b- to inform about the value of the tunnel project