Which course are you taking?
You can change this later with the Level button at the top.
Before the bench unlocks
Speed
⏸ Paused. Press P or Resume.
How to use the bench (mouse, touch, or keyboard)
- Move the lamp: drag it along its track, use the slider, or press ← → (hold Shift for 5 cm steps).
- Count a trial: press Start (or S), then tap the big button (or press Space) every time a bubble leaves the cut end. The stopwatch stops at the time you chose. Then press Record trial.
- Wait first: after any change, give the plant about 2 minutes to settle before you count. The green bar under the stopwatch tells you when.
- Other keys: P pause · R reset the trial · + / − zoom in and out · H help. Enter presses a focused button (Space is saved for counting).
- Zoom: the buttons at the top, the + / − on the picture, or pinch on a touch screen or trackpad.