What are the full names of the customer who gave River City a 5-star?
full name = First, Last; River City refers to BrandName = 'River City'; 5-star refers to StarRating = 5;
SELECT T1.First, T1.Last 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 T3.BrandName = 'River City' AND T2.StarRating = 5