human
Considering the provided database schema and associated query, produce SQL code to retrieve the answer to the query. 
###Database Schema: Wheel arrangement, Manufacturer Serial numbers, Year introduced MRWA, Quantity made, Quantity preserved, Year(s) withdrawn
###Question: What was the year the MRWA with a wheel arrangement of 4-6-2 was introduced?
gpt
SELECT Year introduced MRWA FROM table WHERE Wheel arrangement = 4-6-2