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

Author Question: Which of the following is true of wavelengths of signals sent into space? A) Wavelengths longer ... (Read 34 times)

cherise1989

  • Hero Member
  • *****
  • Posts: 555
on: Jul 27, 2018
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
Reply #1 on: Jul 27, 2018
Answer to Question 1

C

Answer to Question 2

C


cherise1989

  • Member
  • Posts: 555
Reply 2 on: Jul 27, 2018
YES! Correct, THANKS for helping me on my review

mcarey591

  • Member
  • Posts: 365
Reply 3 on: Yesterday
:D TYSM

« previous next »
 

Did you know?

More than 30% of American adults, and about 12% of children utilize health care approaches that were developed outside of conventional medicine.

Did you know?

To combat osteoporosis, changes in lifestyle and diet are recommended. At-risk patients should include 1,200 to 1,500 mg of calcium daily either via dietary means or with supplements.

Did you know?

Complications of influenza include: bacterial pneumonia, ear and sinus infections, dehydration, and worsening of chronic conditions such as asthma, congestive heart failure, or diabetes.

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?

Asthma is the most common chronic childhood disease in the world. Most children who develop asthma have symptoms before they are 5 years old.

Oasis in space: earthrise over the moon's horizon. Oasis in space: earthrise over the moon's horizon.
True-color view of Mars seen through NASA's Hubble Space Telescope in 1999 True-color view of Mars seen through NASA's Hubble Space Telescope in 1999
An electrocardiogram (ECG, EKG) is a commonly used procedure in which the electrical events associat An electrocardiogram (ECG, EKG) is a commonly used procedure in which the electrical events associat
Space Space
Space-Beach Wallpaper Space-Beach Wallpaper
Spitzer Space Telescope Spitzer Space Telescope
Video: Bulk flow - factors that influence bulk flow

For a complete list of videos, visit our video library