Please list the brands of all the root beer that Frank-Paul Santangelo had purchased on 2014/7/7.
brands of the root beer refers to BrandName; purchased on 2014/7/7 refers to transactiondate = '2014-07-07';
SELECT DISTINCT T4.BrandName FROM customers AS T1 INNER JOIN `transaction` AS T2 ON T1.CustomerID = T2.CustomerID INNER JOIN rootbeer AS T3 ON T2.RootBeerID = T3.RootBeerID INNER JOIN rootbeerbrand AS T4 ON T3.BrandID = T4.BrandID WHERE T1.First = 'Frank-Paul' AND T1.Last = 'Santangelo' AND T2.TransactionDate = '2014-07-07'