Sub-light Speed

Sub-light Speed is an Earth Badge on Khan Academy. It gives a bonus of 1,500 free Energy points.

How to Obtain this Badge
To earn this badge you have to quickly & correctly answer 42 skill problems in a row (time limit depends on skill difficulty) in a skill. This badge can be earned multiple times.

Fact:
The easiest skill to get this badge in is 1-digit Addition.