How many stars did Urijah Faber rate for Frostie?
stars refers to StarRating; Frostie refers to BrandName = 'Frostie';
SELECT T2.StarRating FROM customers AS T1 INNER JOIN rootbeerreview AS T2 ON T1.CustomerID = T2.CustomerID INNER JOIN rootbeerbrand AS T3 ON T2.BrandID = T3.BrandID WHERE T1.First = 'Urijah' AND T1.Last = 'Faber' AND T3.BrandName = 'Frostie'