it isn't spread, it develops from other causes
why light spread causes different temperature
When one part of a vibration causes air particles to spread out, they form ararefaction
When one part of a vibration causes air particles to spread out, they form ararefaction
That's how they spread their seed.
rising molten magma
The spread of English can be attributed to historical factors such as British colonization and imperialism, the rise of the United States as a global superpower after World War II, the influence of English in international trade and diplomacy, and the popularity of English-language media and entertainment. Additionally, the flexibility and adaptability of the English language have also contributed to its widespread use as a lingua franca.
The shortening in them melts and causes them to spread.
the spred of bactriea is caused by sickness
a convex mirror
foam
Convection currents