What did the Roman Empire use the volcanic ash for that came
from the local volcanoes

To make concrete

Concrete is the most widely used construction material in the world. ... “A natural process in the caldera produces lime and forms concrete-like rocks by mixing it with ash – the same volcanic ash that Romans used.” That mixing creates rock that is compositionally similar to Roman concrete, but stronger.

Romans used volcanic ash and mixed it with lime to make this iconic material,” she explained. “A natural process in the caldera produces lime and forms concrete-like rocks by mixing it with ash – the same volcanic ash that Romans used."

the correct answer is “opportunity cost”. opportunity cost is what a company misses out because it decided in one option over another one. in this case, the company decided to invest in building a factory so it gave up another possible benefit or profit in order to achieve success with the factory.  

trade-off is not the correct answer since it is a situation in which you accept losing something in return for benefits in other areas.

and finally, consequence is a general term used to accept what it comes when you make a decision. it can be a positive or negative consequence depending if the decision you took was the correct one.  

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