i think you mean antibiotic ... but Alexander Fleming was the one who advanced the antibiotic (world) and was responsible for creating these categories of medicine... this affected the 20th century because millions of people use antibiotics everyday and without them... many diseases would still affect people without a cure
Answer:
Why did some believe that US expansion was needed to preserve the "American Spirit?" They thought that America would need a strong navy to protect the markets. Also, in Alfred Mahan's book, The Influence of Sea Power Upon History, he says that America's future would rely on gaining new markets abroad.
Explanation:
I think it's the telephone because it allows people to communicate better and customers or workers don't have to walk up to everyone and disturb them. You may elaborate more on this with your own opinion
Answer:
A civilization is a complex culture in which large numbers of human beings share a number of common elements. Historians have identified the basic characteristics of civilizations. Six of the most important characteristics are: cities, government, religion, social structure, writing and art.
