A bank has two clients who are both importing goods from the same foreign supplier. The first client is importing goods worth $10 million and is paying for the goods in 90 days. The second client is importing goods worth $20 million and is paying for the goods in 180 days. The bank has lent money to both clients and wants to calculate its exposure to foreign currency risk for these two transactions. The exchange rate is 1.5 foreign currency units to 1 US dollar. What is the bank's exposure to foreign currency risk in US dollars?