In a collection of 60 vintage comic books, 20 are from the 1960s, 15 are from the 1970s, and 10 are from the 1980s. Of the remaining comic books, one-third are from the 1950s and two-thirds are from the 1990s. If a pie chart is created to represent this data, what is the measure in degrees of the central angle for the sector representing comic books from the 1950s?
25
30
35
40
45
