This topic contains a solution. Click here to go to the answer

Author Question: Which of the following is true of O and B stars? A) Their parallax is too small to measure. B) ... (Read 89 times)

asan beg

  • Hero Member
  • *****
  • Posts: 570
Which of the following is true of O and B stars?
 
  A) Their parallax is too small to measure.
  B) They are not found in associations.
  C) They reveal parts of six spiral arms near the Sun.
  D) Their distances cannot be measured by spectroscopic parallax.

Question 2

The mass of the Milky Way Galaxy can be estimated by:
 
  A) the orbital motions of the stars within the galaxy.
  B) the mass of the planets in the Solar System.
  C) the luminosity of the stars of the neighboring galaxies.
  D) the concept laid down by the spiral density wave theory.



Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
Marked as best answer by a Subject Expert

yasmin

  • Sr. Member
  • ****
  • Posts: 319
Answer to Question 1

A

Answer to Question 2

A



asan beg

  • Hero Member
  • *****
  • Posts: 570
Both answers were spot on, thank you once again



yasmin

  • Sr. Member
  • ****
  • Posts: 319

 

Did you know?

The use of salicylates dates back 2,500 years to Hippocrates's recommendation of willow bark (from which a salicylate is derived) as an aid to the pains of childbirth. However, overdosage of salicylates can harm body fluids, electrolytes, the CNS, the GI tract, the ears, the lungs, the blood, the liver, and the kidneys and cause coma or death.

Did you know?

Many medications that are used to treat infertility are injected subcutaneously. This is easy to do using the anterior abdomen as the site of injection but avoiding the area directly around the belly button.

Did you know?

In women, pharmacodynamic differences include increased sensitivity to (and increased effectiveness of) beta-blockers, opioids, selective serotonin reuptake inhibitors, and typical antipsychotics.

Did you know?

Though Candida and Aspergillus species are the most common fungal pathogens causing invasive fungal disease in the immunocompromised, infections due to previously uncommon hyaline and dematiaceous filamentous fungi are occurring more often today. Rare fungal infections, once accurately diagnosed, may require surgical debridement, immunotherapy, and newer antifungals used singly or in combination with older antifungals, on a case-by-case basis.

Did you know?

The strongest synthetic topical retinoid drug available, tazarotene, is used to treat sun-damaged skin, acne, and psoriasis.

For a complete list of videos, visit our video library