The fore arm has two bones - the Radius and the Ulna
long bones fore-arm bones
Radius and Ulna
2 simple justice
Oh yes. If you did not have bones in your arms, they would be tentacles.
Radius/ulna
just one - the number 4 is spelt 'four'.
Example of vertebrates (having a spinal column) could be humans, whose fore limbs are arms, as we stand upright. Then there are animals like the horse, whose fore limbs (indeed all four limbs) are actually legs.
disarm
i so you can turn your arm and leg
fore arms
Three bones in your arms
the elbow bone the toher bones and the hand bones