AR-Receipt cross currency rate

Hi

Am working on this issue with AR, the transaction is in BRL currency and the receipt is in USD. I want it to use the rates that have been defined in the setup tables. But when applying the receipt there is a field that requires cross currency rate, I don't want this to show up I wasn't to use the setup currency

 

These are the rates defined in the system – Setup screen. Assumption is that the rate defined here will apply if transaction date  is any of these Feb dates these rates should apply

   

Transaction is created in BRL, see dates of the transaction