Detailed Instructions: In this task, you're given a statement, further information available on a particular linked term from the statement, and a question. Your job is to generate the answer to the question by using the information provided. If there is no clear answer obtainable, output 'none'.
Q: Context: In 1286, Rudolph of Habsburg granted Veldenz town and market rights Link Information: Rudolf I, also known as Rudolf of Habsburg (, ; 1 May 1218 15 July 1291), was Count of Habsburg from about 1240 and King of Germany from 1273 until his death Question: How long did Rudolph have rule?
A:
Answer: 18