This topic contains a solution. Click here to go to the answer
« previous next »

Author Question: Which of the following analogies best describes how the structure of the galaxy's spiral arms is ... (Read 31 times)

bb

  • Hero Member
  • *****
  • Posts: 544
on: Jul 27, 2018
Which of the following analogies best describes how the structure of the galaxy's spiral arms is maintained?
 
  A) Like military jets flying in formation above a football stadium, the stars in the spiral arms keep a spiral-shaped formation as they orbit the galaxy.
  B) Like cars slowing in traffic to look at an accident, stars slow as they pass through the spiral arms.
  C) Like a coiling rope, the spiral arms wind up tighter with every galactic rotation.
  D) Like the fins of a giant pinwheel toy, the spiral arms carry a set of bright stars around as they sweep through the galaxy.

Question 2

How did Eratosthenes estimate the size of Earth in 240 B.C.?
 
  A) by observing the duration of a solar eclipse
  B) by measuring the size of Earth's shadow on the Moon in a lunar eclipse
  C) by comparing the maximum altitude of the Sun in two cities at different latitudes on the summer solstice
  D) by sending fleets of ships around Earth
  E) We don't know how he did it since all his writings were destroyed.


Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
Marked as best answer by a Subject Expert

lauravaras

  • Sr. Member
  • ****
  • Posts: 347
Reply #1 on: Jul 27, 2018
Answer to Question 1

B

Answer to Question 2

C


bb

  • Member
  • Posts: 544
Reply 2 on: Jul 27, 2018
YES! Correct, THANKS for helping me on my review

daiying98

  • Member
  • Posts: 354
Reply 3 on: Yesterday
:D TYSM

« previous next »
 

Did you know?

Of the estimated 2 million heroin users in the United States, 600,000–800,000 are considered hardcore addicts. Heroin addiction is considered to be one of the hardest addictions to recover from.

Did you know?

The average person is easily confused by the terms pharmaceutics and pharmacology, thinking they are one and the same. Whereas pharmaceutics is the science of preparing and dispensing drugs (otherwise known as the science of pharmacy), pharmacology is the study of medications.

Did you know?

Though newer “smart” infusion pumps are increasingly becoming more sophisticated, they cannot prevent all programming and administration errors. Health care professionals that use smart infusion pumps must still practice the rights of medication administration and have other professionals double-check all high-risk infusions.

Did you know?

The oldest recorded age was 122. Madame Jeanne Calment was born in France in 1875 and died in 1997. She was a vegetarian and loved olive oil, port wine, and chocolate.

Did you know?

There are over 65,000 known species of protozoa. About 10,000 species are parasitic.

Function and structure of aquaporin Function and structure of aquaporin
The elliptical galaxy Centaurus A at visible, far-infrared and x-ray wavelengths. The elliptical galaxy Centaurus A at visible, far-infrared and x-ray wavelengths.
X-Ray Crystallography Helped Reveal the Structure of DNA X-Ray Crystallography Helped Reveal the Structure of DNA
Transfer RNA (tRNA) Structure Transfer RNA (tRNA) Structure
Hold baby’s hands and (A) cross arms over chest and then (B) open out to the sides. Repeat several ... Hold baby’s hands and (A) cross arms over chest and then (B) open out to the sides. Repeat several ...
IgG Antibody Structure IgG Antibody Structure
Video: Predator- prey competition and symbiosis

For a complete list of videos, visit our video library