Hbr + h₂so₄ so₂ + br₂ + h₂o
what is the oxidation number of the oxidizing agent?
what is the oxidation number of the reducing agent?

The reaction equation is:
HBr + H₂SO₄ → SO₂ + Br₂ + H₂O

An oxidizing agent is a substance that itself becomes reduced and oxidizes the other chemical species in the reaction mixture. A reducing agent is similar, except that it becomes oxidized and reduces the other substance. 
In the reaction, the valency of bromine changes from -1 to 0, so it is oxidized, making it the reducing agent. The valency of sulfur changes from +6 to +4, so it is reduced, making it the oxidizing agent.

Organisms are more likely to be more preserved in mud than sand because mud is moist and wet, while sand is very dry.

8.7 degrees celsius and 15.6 degrees fahrenheit