World 2 · Diesel, Rotary and Electric · 13 min · PRO
Petrol vs diesel
Spark or squeeze
PRO · Engine Room
World 2: Diesel, Rotary and Electric is part of PRO
The first world of Engine Room is free. PRO opens the other 20 lessons in 6 worlds — simulations, quizzes and all.
PRO includes
- All 60 labs — every world, every lesson
- Practice exams and certificates
$8.33/mo, billed yearly ($99.99) · or $39.99 monthly