The eaths radius is the correct answer, if you need proof look at nasa's website
13.6) When any boat displaces a weight of water equal to its own weight, it floats.
Search Results<span>By simply wrapping wire that has an electrical current running through it around a nail, you can make an electromagnet. When the electric current moves through a wire, it makes a magnetic field. ... You can make a temporary magnet by stroking apiece of iron or steel (such as a needle) along with a permanent magnet.
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Let the data is as following
mass of payload = "m"
mass of Moon = "M"
now we know that we place the payload from the position on the surface of moon to the position of 5r from the surface
So in this case we can say that change in the gravitational potential energy is equal to the work done to move the mass from one position to other
so it is given by

we know that


now from above formula


so above is the work done to move the mass from surface to given altitude
Answer:
Being a plane mirror the Image is formed 3 metres beyond the mirror . So total distance is 3+3 = 6metres