It's a strange question to ask, I'd include some of the following:
- Air resistance can slow down a projectile, changing its path (not used in HSC calculations) --> lowers maximum height, range and time of flight.
- Initial velocity --> higher values increase the range when angle against horizontal is not 90degrees, increases maximum height, increases range and time of flight (when angle against horizontal is not 0 degrees).
- Strength of gravitational field (~9.8ms-2 on Earth's surface) --> higher values decrease time of slight (and thus, range) and maximum height.
- Angle of projection against the horizontal