Definition: In this task, you're given a passage, 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'.
Input: Passage: William Havemeyer (1770-1851) left Germany at age 15 and arrived in New York City after learning the trade of sugar refining in London. In New York he managed a sugar house on Pine Street before opening his own refinery on Vandam Street with his brother, Frederick Christian Havemeyer, who had come to New York in 1802. Together the two brothers operated the W. & F.C. Havemeyer Company sugar refineries, before passing the business on to their sons. His son William Frederick Havemeyer, retired from the sugar refining business in 1842 and entered politics, eventually serving three terms as Mayor of New York. In 1855 the family relocated their refineries to Brooklyn, where they remained as the business grew to acquire a commanding share of the United States sugar refining market under the leadership of Frederick's grandson, Henry Osborne Havemeyer. The Havemeyer refineries were incorporated as the American Sugar Refining Company in 1891 and became known as Domino Sugar in 1900. In the 20th century several of the family's members made notable contributions to the arts. Henry Osborne Havemeyer and his wife Louisine Havemeyer made large bequests to the Metropolitan Museum of Art and their daughter Electra Havemeyer Webb founded the Shelburne Museum.
 Link Information: William Frederick Havemeyer (February 12, 1804 – November 30, 1874)  Question: How old was William Havemeyer's son when he retired from the sugar refining business?
Output:
Answer: 38