Related Clues:
- Light unit
- It might ask 'What comes next?'
- Bit of light
- Brightness measure
- Light-flow measure
- Projector unit
- Hurdle for Mensa membership
- Grade school administration, maybe
- Measurer of brainpower
- Unit of brightness
- Many people get 100 on it
- Unit for measuring flow of light
- Brightness detector
- Sharpness gauge
- Measure of brainpower