Nearly all of the oxygen in the Earth's atmosphere was originally ...

[bobthebuilder]

Nearly all of the oxygen in the Earth's atmosphere was originally produced by photosynthesis in the leaves of trees that covered the continents 3.5 billion years ago.
 
  Indicate whether the statement is true or false

Question 2

What is the spectral type of a main sequence star with a luminosity 100 times greater than the sun?
 
  A) G B) A C) M D) O

[rachel]

Answer to Question 1

FALSE

Answer to Question 2

B

[bobthebuilder]

Thanks for the timely response, appreciate it

[atrochim]

Gracias!