contestada

U.S. Birth Rate, 1950-2000

Year
Birth Rate
(per 1000 population)
1950
24.1
1960
23.7
1970
18.4
1980
15.9
1990
15.7
2000
14.7
Source: World Almanac 2003

Is the relation (year, birth rate) a function? Explain.
a.
No, there is a year with two birth rates paired with it.
b.
Yes, each year is paired with only one value for the birth rate.
c.
No, two years have a birth rate of over 20.
d.
No, there are no negative birth rate values.