As a star forms, the photosphere first appears: A) when the planetary nebula is expelled. B) ...

Author Question: As a star forms, the photosphere first appears: A) when the planetary nebula is expelled. B) ... (Read 24 times)

Lisaclaire

Hero Member
Posts: 569

on: Jul 27, 2018

As a star forms, the photosphere first appears:

A) when the planetary nebula is expelled.
B) when the protostar forms.
C) when contraction slows down.
D) when nuclear fires ignite.
E) when the star reaches the main sequence.

Question 2

The particles which enter into chemical reactions are the atom's:

A) protons.
B) neutrons.
C) positrons.
D) electrons.
E) mesons.

amandanbreshears

Sr. Member
Posts: 320

Reply #1 on: Jul 27, 2018

Answer to Question 1

B

Answer to Question 2

D

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