Question: What is the date of death of Carl Hellmuth Hertz's father?
Sentence (from "Carl Hellmuth Hertz"): Carl Hellmuth Hertz (also written Carl Helmut Hertz, October 15, 1920 – April 29, 1990) was a German physicist known primarily for being involved in the development of inkjet technology and ultrasound technology.
Relevant evidence: No