Answer:
Yes, there is a riskless arbitrage opportunity
Explanation:
Arbitrage is defined as the simultaneous buying and selling of assets or derivatives in order to take advantage of differing prices for the same asset.It is the technique of buying an asset cheap in place A and immediately selling it at a higher price in place B.
Since XYZ has an infinite trading horizon, it can simultaneously trade with other firms in other locations at higher costs. No risk is attached to this kind of transaction since the transactions are happening simultaneously in different locations. The profit is guaranteed and even small profits in the different transaction is worth the trade.