Short answers, pulled from the story.
The first official paid television advertisement aired on the 1st of July 1941, at 2:30 p.m. on New York station WNBT, before a baseball game between the Brooklyn Dodgers and Philadelphia Phillies. It was an announcement for Bulova watches, for which the company paid between $4.00 and $9.00.
The first UK television advertisement aired on ITV on the 22nd of September 1955, advertising Gibbs SR toothpaste.
The US television advertising market was estimated at $69.87 billion in ad spending for 2018.
Data from the SkyView panel of more than 33,000 UK Sky+ households showed that DTR owners watched 82% of their television as live broadcast with no ad-skipping. Across all viewing, DTR owners ended up watching 2% more ads at normal speed than before they owned the device.
The use of original popular recordings in US television advertisements began in earnest in 1985, when Burger King used Aretha Franklin's own recording of "Freeway of Love." Before the late 1980s, the cost of licensing original recordings in the US made cover versions the standard practice.
Ronald McDonald was retired from advertising in 2016 after 53 years of use. The retirement came in the context of widespread public clown-related anxiety and followed a letter signed by 550 physicians, submitted five years earlier, arguing that a clown mascot targeting children for fast food was unethical.