input question: What is the final step of the following process: -  Particles in the environment interact with rocks - The particles remove small pieces of the rock each time they touch the rocks - The particles continue to hit, brush against, or grow against the rocks - The rock eventually is broken apart by this contact - The pieces of the rock are now small rocks???
output answer: The rock pieces are worn away into smaller and smaller pieces by the same forces

input question: What is the final step of the following process: -  Humans are born as babies - Babies become infants - Infants become children - Children learn skills - Children become teenagers - Teenagers undergo puberty - Teenagers become adults - Adults have children - Adults become elderly???
output answer: Elderly humans die.

input question: What is the final step of the following process: -  Chemicals like sulfur dioxide and nitrogen are released into the air - These substances rise into the high atmosphere - They react with water and oxygen - This creates a more acidic rain???
output answer: The rain with the high acid content falls.

input question: What is the final step of the following process: -  A type of coal must be chosen before the heating can start - The coal is broken down to a smaller material - The coal particles mix with hot air and move in to a boiler - Water in the boiler is pumped and produces steam with the coal - Steam powers turbine blades, which magnetically charge wire coals???
output answer:
The water returns back in to its chamber and the process is repeated