Engine: General Subjects

1. A Valves "C", "J", "K", "L", "M" open, valves "A", "B", "D", and "H" closed.
2. B Valves "D", "H", "J", "K", "L", "M" open, valves "I", "G", "F", and "E" closed.
3. C Valves "H", "J", "K", "L", "M" open, valve "D" closed.
4. D Valves "J", "K", "L", "M" open, valves "D" and "H" closed.

Tip: press A-D to answer