Using concepts of quadratic equation, we have that:
a) The age of unmarried women with the highest birth rate 29 years.
b) The highest birth rate of unmarried women is of 65 births per 1000 unmarried women.
c) B(40) = 25.43, which means that the birth rate of unmarried women of age 40 is of 25.43 births per 1000 unmarried women.
The birth-rate for women of age a is given by:

Which is a quadratic equation with coefficients 
Item a:
The age with the highest value is the a-value for the vertex, which is:

The age of unmarried women with the highest birth rate 29 years.
Item b:
The rate is B(29), which is:

The highest birth rate of unmarried women is of 65 births per 1000 unmarried women.
Item c:

B(40) = 25.43, which means that the birth rate of unmarried women of age 40 is of 25.43 births per 1000 unmarried women.
A similar problem is given at brainly.com/question/24626341