Use the following table definitions to answer the question below. customer(custno, name, address, city, state, zip, phone, income) asset(assetno, assetdesc, assettype) service(servno, servdesc, servrate) employee(empno, empname, emptitle) pricehistory(assetno, date, price) FOREIGN KEY assetno REFERENCES asset charge(chargeno, custno, servno, starttime, endtime, empno, billed, amtpaid) FOREIGN KEY custno REFERENCES customer FOREIGN KEY servno REFERENCES service FOREIGN KEY empno REFERENCES employee holding(custno, assetno, qty) FOREIGN KEY custno REFERENCES customer FOREIGN KEY assetno REFERENCES asset trade(tradeno, custno, ossetno, qty, price, date, type, status) FOREIGN KEY custno REFERENCES customer FOREIGN KEY assetno REFERENCES asset What table contains a combined primary key that represents a M-N relationship?