# night light quiz
change the brightness of the BBC micro:bit.
## Name
## Directions
Use this activity document to guide your work in the [night light tutorial](/lessons/night-light/activity)
Answer the questions while completing the tutorial. Pay attention to the dialogues!
## 1. Describe what "led->set brightness" does ?
## 2. If the picture below is the BBC micro:bit, write the code that sets all the LEDs to full brightness and turns on all the LEDs
![](/static/mb/lessons/night-light-0.png)
## 3. If the picture below is the BBC micro:bit, write the code that sets the screen brightness to 50% (128) and turns on all the LEDs.
![](/static/mb/lessons/night-light-1.png)
## 4. If the picture below is the BBC micro:bit, write the code turns off all the LEDs.
![](/static/mb/lessons/night-light-2.png)