What is the total number of drivers who have cars constructed by Mercedes-Benz?
CREATE TABLE table_18893428_1 (driver VARCHAR, constructor VARCHAR)
SELECT COUNT(driver) FROM table_18893428_1 WHERE constructor = "Mercedes-Benz"
### Context: CREATE TABLE table_18893428_1 (driver VARCHAR, constructor VARCHAR) ### Question: What is the total number of drivers who have cars constructed by Mercedes-Benz? ### Answer: SELECT COUNT(driver) FROM table_18893428_1 WHERE constructor = "Mercedes-Benz"