Answer: 4550 Joules
The formula for potential energy in gravitational field is as follows:

Answer:
my favourite song is hym to the sea. That song reminds me of the innocent people who lost their lives in titanic a century ago. If I was the writer of that song ,i would not change the title of that song because I can feel the sound of ocean when I listen to that song.
If both the net force and the mass are doubled, the acceleration will be unchanged.