Answer: In 1869 Russian chemist Dimitri Mendeleev started the development of the periodic table, arranging chemical elements by atomic mass. He predicted the discovery of other elements, and left spaces open in his periodic table for them
Explanation:
Answer:A
Explanation:you can't determine if someone's a good person based on appearance
<span> d. Prevent the spread of communism outside of Eastern Europe.</span>
Answer:
B
He didn't like the science teacher because he smelled like a pine tree.
