The reducing agent in this redox equation?

[ally1h]

Homework Statement

Which is the reducing agent in this equation, if any?

Cr2O7 2- + 2OH- --> 2CrO4 2- +H2O

Homework Equations

The Attempt at a Solution

After giving the elements their oxidation numbers I found the reducing agent to be Cr2O7 2-

Is this correct?

 

[Borek]

Which element changes oxidation number? From what to what?