EBQ

Hi,

Can any one help me explain the meaning of each component in EBQ formula:
EBQ=?((2 CO D)/(CH(1-D/R)))

As per EBQ definition, it is the economic order quantity ? In question 6.17 in BPP pratice book, economic production is required. But the answer is about EBQ. What is the relationship between economic production run and EBQ?
what does production rate (R) in this formular meaning?

Thank you very much for your help