. Which industry is often referred to as the back bone of modern industry and why?

Explanation:

Steel is called the backbone of the modern industry because almost everything we use is either made of steel or has been made with machinery or tools made out of steel. The steel industry is basically the feeder industry, whose products are the raw materials for other industries.

well considering i can't see the graph, it's probably prices

the invasive species was introduced due to commercial purpouses, as there was a demand for fur clothes and hence, a business opportunity connected to this product. actually, it was when the nutrias scaped, causing harm to the us ecosystems when they acquired the status of invasive species. in this case they have caused an environmental problem, but it could have affected also economic interests or even human health.