The two discoveries that brought a revolution in early man's life are:
1) Agriculture - It helped the early man to produce its own food. this innovation made possible new flux of innovations and ideas the husbandry and domestication of all modern cattle and pets (except dogs), the formation of soldiers and wars, the money, the origin of religion, writing and all the very basis of modern life. Developing all these new outcomes would be impossible without the cooperation and organized structure of agricultural societies.
2) Language and paintings - Language helps them to communicate with each other and painting which they did at that time helped Historians today to know about their life, language, etc.
Answer:
Despite building cities, they did not construct pyramids. (This one is NOT true).
Explanation:
The Mayans are actually well know for the construction of their majestic pyramids.
Option (C) castes is the correct answer.
The number of votes cast for president rose from about 350,000 in 1824 to over 2.4 million in 1840. Universal Male Suffrage, Party Nominating Conventions, Popular Election of the President, Two-Party System, Rise of Third Parties, More Elected Offices, Popular Campaigning, Spoils System, and Rotation of Officeholders all lead to changes in U.S. politics between 1824 and 1840.
I have no clue but none of those are correct for sure