In the 1950s, Stanley Miller and Harold Urey conducted experiments in which they fired electrical sparks in the presence of a mixture of different gases. How d these experiments contribute to the theory of the origins of life on earth? A They determined that the age of organic molecules can be measured by the half-life of isotopes

B They showed that organic molecules could be formed from materials nypothesized to be available in the Earth's early atmosphere

C They proved that organic molecules formed from the accumulation of debris from space

D They discovered that organic molecules would not have formed without the presence of oxygen in the atmosphere​

biology spring assessment 2020-2021

80 points pls brainliest 1. what does a red shift mean? blue shift? 2. describe the big bang theory. according to this theory, how old is the universe? 3. scientists believe the universe is expanding. what is the evidence that supports this? 4. describe a nebula. 5. describe the 3 types of galaxies. what is a barred spiral galaxy? 6. what is a light year? how far is alpha centauri from earth? 7. describe the universal law of gravitation. be sure to include gravitational force between two objects. 8. describe the planets’ orbits around the sun. 9. what is the asteroid belt? where is it located? 10. describe rotation and revolution of earth. what determines an earth day and year? 11. how do galaxies exist? 12. compare and contrast the inner and outer planets. 13. what causes the seasons?