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

Author Question: Which of the following is true of wavelengths of signals sent into space? A) Wavelengths longer ... (Read 48 times)

cherise1989

  • Hero Member
  • *****
  • Posts: 555
Which of the following is true of wavelengths of signals sent into space?
 
  A) Wavelengths longer than 100 cm are absorbed in Earth's atmosphere.
  B) The interval between the 21-cm spectral line of neutral hydrogen and the 18-cm line of OH has very high background interference.
  C) Wavelengths longer than 100 cm get lost in the background noise of the Milky Way Galaxy.
  D) The interval between the 21-cm spectral line of neutral hydrogen and the 18-cm line of OH is narrow and can be monitored easily.

Question 2

Which of the following is true of natural selection?
 
  A) It is a random occurrence.
  B) It does not occur in most species of organisms.
  C) It is directed by changes in the environment.
  D) It does not lead to evolution of a species.



Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
Marked as best answer by a Subject Expert

Alyson.hiatt@yahoo.com

  • Sr. Member
  • ****
  • Posts: 354
Answer to Question 1

C

Answer to Question 2

C




cherise1989

  • Member
  • Posts: 555
Reply 2 on: Jul 27, 2018
Great answer, keep it coming :)


miss_1456@hotmail.com

  • Member
  • Posts: 289
Reply 3 on: Yesterday
Excellent

 

Did you know?

Asthma-like symptoms were first recorded about 3,500 years ago in Egypt. The first manuscript specifically written about asthma was in the year 1190, describing a condition characterized by sudden breathlessness. The treatments listed in this manuscript include chicken soup, herbs, and sexual abstinence.

Did you know?

Elderly adults are at greatest risk of stroke and myocardial infarction and have the most to gain from prophylaxis. Patients ages 60 to 80 years with blood pressures above 160/90 mm Hg should benefit from antihypertensive treatment.

Did you know?

Colchicine is a highly poisonous alkaloid originally extracted from a type of saffron plant that is used mainly to treat gout.

Did you know?

Calcitonin is a naturally occurring hormone. In women who are at least 5 years beyond menopause, it slows bone loss and increases spinal bone density.

Did you know?

Cutaneous mucormycosis is a rare fungal infection that has been fatal in at least 29% of cases, and in as many as 83% of cases, depending on the patient's health prior to infection. It has occurred often after natural disasters such as tornados, and early treatment is essential.

For a complete list of videos, visit our video library