2H2+O2----->2H2O. I hope this helps
Work is measured in joules. hope this helps!
All animals can be dangerous and they would fight for their family. (This might be wrong)
1st and 4th options are suitable answers, as these 2 changes are not exactly physical changes as it cant return back to original form and as well as its not cooling, so I feel its 1st and 4th options
They have a mass for the particles
There are no totally elastic collisions
There are intermolecular forces
