Need help with this problem

The percentage of women in the 20-24 age group who have never married went from 55% in 1970 to 73% in 2000. Let 1970 be year 0 and 2000 be year 30

a) Find and intercept the slope of the line through the points (0,55) and (30,73) ........I got this one

b) Find the equation of the line in part (a)

c) What is the meaning of the y-intercept?

d) Use the equation to predict the percentage in 2010.

e) If this trend continues,then in what year will the percentage of women in the 20-24 age group who have never married reach 100%