Boron, Aluminum, Gallium, Indium, Thallium
Sattelites don't need any fuel to stay in orbit. The applicable law is...."objects in motion tend to stay in motion". Having reached orbital velocity, any such object is essentially "falling" around the earth. Since there is no (or at least very little) friction in the vacuum of space, the object does not slow.... It simply continues.
Sattelites in "low" earth orbit do encounter some friction from the very thin upper atmosphere, and they will eventually "decay".
:)
The boy's momentum is 160 kg*m/s north.
The formula of momentum is p = mv, where p is momentum.
p = 40 kg * 4m/s north
p =160 kg*m/s north<span>Thank you for posting your question. I hope you found what you were after. Please feel free to ask me more.</span>