Author Question: O stars must be formed in spiral arms because _____. a. they do not live long enough to move out ... (Read 18 times)

joe

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O stars must be formed in spiral arms because _____.
 
  a. they do not live long enough to move out of the arm
 b. the dust clouds they form from are only found there
 c. all stars are formed in spiral arms
 d. they are only found in spiral arms their gravitational forces takes them to that location
  e. they are left behind and found in the region behind the spiral arm

Question 2

What is the escape velocity from the Moon for a lunar landing module sitting on the Moon's surface? Hints: ; The mass of the Moon is 7.2  1022 kg; its radius is 1738 km; G = 6.67 10-11 m3/s2/kg
 
  a. 2.3 m/s
 b. 23 m/s
 c. 2.3 km/s
  d. 11 km/s
 e. 23 km/s



komodo7

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Answer to Question 1

a

Answer to Question 2

c



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