Progressives lived in cities and believed that government could be tool for change they believed social problems were caused by industrialization and urbanization.
The best option from the list would be that "<span>b. The United States began to build up its military and to stockpile weapons," since this was part of the inevitable "Arms Race" that took place between the US and the USSR. </span>
From 1300s to 1500s, which is about two centuries, Japan tore itself apart in the feudal wars and all the civil conflicts. Due to Minamoto's victory, Japan transitioned to medieval feudalism and power rested upon two shogun regimes, the Kamakur and Ashikaga.
Male teachers made about $863 per year and female teachers made about $422 per year.