28. The life cycle of a star:
Stellar Nebula
↓
Average Star
↓
Red Giant
↓
Planetary Nebula
↓
White Dwarf
Stellar Nebula
↓
Massive Star
↓
Red Supergiant
↓
Supernova
↓
Neutron Star
Stellar Nebula
↓
Massive Star
↓
Red Supergiant
↓
Supernova
↓
Black Hole