The Ohio River, as the dividing line between<span> slave states, </span>south,<span> and free-soil states, </span>north.
The book that brought the public's attention to damage caused by pollution in the early 1960's is Silent spring. The correct option among all the options that are given in the question is option "b". This book was actually written in the year 1962 by Rachel Carson. It was a book concerning environmental science.
Man you will get no where wwithout no statements
