Answer
$ y=0$
Work Step by Step
We are given the function $ P(x)=\dfrac{72,900}{100x^2+729}$
We see that when $ x \to \infty $, the function has a horizontal asymptote because the degree of the numerator is smaller than the degree of the denominator.
This implies that when the number of years of education increases to a high number, the percentage of unemployed people becomes $0$.
Therefore, $ y=0$