According to our modern science, which of the following best ...

[Charlie]

According to our modern science, which of the following best explains why the vast majority of the mass of our solar system consists of hydrogen and helium gas?
 
  A) Hydrogen and helium are the most common elements throughout the universe, because they were the only elements present when the universe was young.
  B) Hydrogen and helium are produced in stars by nuclear fusion.
  C) All the other elements escaped from the solar nebula before the Sun and planets formed.
  D) All the other elements were swept out of the solar system by the solar wind.

Question 2

A planet's density can be measured by combining
 
  A) Doppler and astrometric observations.
  B) Doppler and transit observations.
  C) spectral observations of the planet's atmosphere.
  D) any method that measures the gravitational tug of the planet on the star.
  E) direct imaging from the new generation of space telescopes.

[gstein359]

Answer to Question 1

A

Answer to Question 2

B

[Charlie]

Gracias!

Excellent