« previous next »

Author Question: As a star forms, the photosphere first appears: A) when the planetary nebula is expelled. B) ... (Read 48 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


Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
« previous next »
 

Did you know?

The U.S. Preventive Services Task Force recommends that all women age 65 years of age or older should be screened with bone densitometry.

Did you know?

More than 50% of American adults have oral herpes, which is commonly known as "cold sores" or "fever blisters." The herpes virus can be active on the skin surface without showing any signs or causing any symptoms.

Did you know?

On average, the stomach produces 2 L of hydrochloric acid per day.

Did you know?

The first oncogene was discovered in 1970 and was termed SRC (pronounced "SARK").

Did you know?

HIV testing reach is still limited. An estimated 40% of people with HIV (more than 14 million) remain undiagnosed and do not know their infection status.

star cluster NGC 6604 star cluster NGC 6604
The Sun is the nearest star to Earth. The Sun is the nearest star to Earth.
Alternative forms of surgeries involving the uterus, ovaries, and fallopian tubes. The solid lines i Alternative forms of surgeries involving the uterus, ovaries, and fallopian tubes. The solid lines i
Distribution and Forms of Precipitation: Snow Distribution and Forms of Precipitation: Snow
Mass Wasting Forms Mass Wasting Forms
Water forms spheres of hydration Water forms spheres of hydration
Video: Protein catabolism - deamination

For a complete list of videos, visit our video library