Small bodies from which the planets are formed is called : Planetesimal.
Planetesimals that have survived to the current day are valuable to scientists since they contain information about the Solar System's formation.
An electron shifts from a lower energy to a higher energy

a)



b)


Using the atomic mass given in the periodic table:




c)


Using the atomic mass given in the periodic table:




This result is an aproximation.
Element Symbol Atomic Mass
Barium Ba 137.327
Hydrogen H 1.00794
Oxygen O 15.9994
Hope this helps, good luck
Answer:
Oxygen
Explanation:
According to my research on Stanley Millers Experiment, I can say that based on the information provided within the question Miller did not use Oxygen as one of the gases in his experiment. On his 1953 experiment the gases used were methane, ammonia, and hydrogen
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