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Author Question: The Drake equation allows us to estimate the number of A) intelligent civilizations that have ... (Read 98 times)

sdfghj

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  • Posts: 552
on: Jul 27, 2018
The Drake equation allows us to estimate the number of
 
  A) intelligent civilizations that have existed in our galaxy during its entire lifetime
  B) habitable planets on which life has arisen
  C) intelligent civilizations capable of traveling to the Earth
  D) intelligent civilizations capable of communicating in our galaxy now

Question 2

A mine railroad car, of mass 200 kg, rolls with negligible friction on a horizontal track with a speed of 10.0 m/s. A 70. kg stunt man drops straight down a distance of 4.0 m, and lands in the car.
 
  How fast will the car be moving after this happens?


nixon_s

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Reply #1 on: Jul 27, 2018
Answer to Question 1

D

Answer to Question 2

7.41 m/s


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