What is the chemical equations for: Steam to
hydrogen using buring magnesium.

It’s the same as when magnesium reacts with liquid water, only faster:

Mg + 2H₂O → MgO + H₂.

The difference is that in water, the reaction has a second step, converting MgO to Mg(OH)₂.

8 m/s because for him to get the same amount of energy as ray is putting out, bobby, who weighs half as much as ray, needs to run twice as fast.

geosphere and hydrosphere.

this is because the geosphere has to do with geological events, while the hydrosphere controls all water on earth.