When going skydiving, categorize each of the following as 'useful' or 'not useful': a parachute, an Acme anvil, a helmet, a go-pro camera, a small herd of miniature ponies, wraparound sunglasses, a backpack full of uranium

Useful: a parachute, a helmet, a go-pro camera, wraparound sunglasses
Not useful: an Acme anvil, a small herd of miniature ponies, a backpack full of uranium