I selected E after 2 minutes.
Yurik, can you pls explain your choice.
I see my mistake)))E it is
1)The distance between r and 0 is 3 times the distance between m and 0
insuff since r and m can be anywhere
2)insuff 12 is a halfway between m and r
together the same))
agree with you E it is
IE IMBA 2010