<span> Lava </span>erupts<span> on the </span>sea floor<span> also the type of rock that cools quickly is Magma and are finer grained and glassy.
Hope this helps</span>
My answer is "Watt per square meter".
F=mg=Gm1m2/r^2
g=Gm2/r^2
g=2Gm2/(2r)^2=2Gm2/4r^2=Gm2/2r^2
So since there is half times the gravity on this unknown planet that has twice earth's mass and twice it's radius, then the person can jump twice as high. 1.5*2= 3m high
I believe that a light bulb releases visible light and a radio antenna releases a radio waves