Benjamin Franklin was an advocate for mild exercise, being an avid swimmer and even building flippers as a boy. He did struggle with health issues, such as obesity and gout. He died of Pluracy in 1790. Angela's facts were fact-checked and corrected. Stephen misspoke about the number of librarians in the US, likely meaning 150,000 instead of 150. Angela referred to a Fermi question regarding the number of golf balls sold in the US each year, which is approximately 30 million. Fermi questions are quickly calculated estimates for hard-to-measure quantities. The Drake equation is an example, used to estimate the likelihood of contacting intelligent alien life.