Many decades ago, the astronomers on the staff of mount wilson and palomar observatories each received about 60 nights per year for their observing programs. today, an astronomer feels fortunate to get 10 nights per year on a large telescope. can you suggest some reasons for this change?

explanation:

could i give you a exaplo that could you?

c because the action was the roller coaster reaches bottom of hill (action) reaction would be blood tends to drain away from head

hope this !

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