The dot plot shows the birth year of everyone who works at Sam’s office. The youngest person who works there was born in 1987. Sam described the data as having a spread from 1965 to 1987, four gaps, a peak at 1984, and a center of 1978. Where did Sam make an error? Birth Year of Employees

A dot plot going from 1965 to 1990. 1966 has 7 dots, 1969 has 2 dots, 1974 has 3 dots, 1975 has 1 dot, 1976 has 3 dots, 1977 has 2 dots, 1977 has 2 dots, 1978 has 5 dots, 1981 has 3 dots, 1983 has 1 dot, 1984 has 8 dots, 1985 has 3 dots, 1986 has 1 dot, 1987 has 1 dot. All other years have 0 dots.
The spread is from 1966 to 1987.
There are 5 gaps.
The peak is at 1985.
The center is at 1977.