Very basic question about 1 EA being able to trade multiple currencies?

[qudcjf7928]

So I am almost finished developing a system that uses mathematical relationship among multiple currencies (usually no more than 4) 

and opens trades on those currencies almost simultaneously to allow hedging ... etc

As it seems that I can only apply 1 EA per chart, my question is

can 1 EA do calculations with MarketInfo of multiple currencies, and

OrderSend and OrderClose of multiple currencies? So, if the system studies the relationship among EUR/USD, GBP/JPY and USD/CAD, marked by a magic number,

can 1 EA include OrderSend and OrderClose for those currencies, except I would apply that EA for those currencies' charts? 

 

p.s. Also, can I backtest that EA on those currencies individually one at a time?  

[Marco vd Heijden]

Yes.

[Wang Yu]

Yes you can monitor and send orders on multi pairs simultaneously. I myself already coded a few dashboard EA to do such kind of job. But backtesting might not be possible as the strategy tester load historical data of one pair only (current chart).