frank runs a shipping business which sends materials across the united states to various manufacturers. one of the manufacturers which frank has dealt with for the last 20 years refuses to pay frank's bill, even though the parties had a signed written contract with clear terms. frank's business continues to thrive, so he forgets about this issue while the pandemic is going on. 5 years later, frank discovers the unpaid bill and wishes to sue the manufacturer. can he do so, and why or why not?