The approximate number of accidents in one month,N, involving drivers between 16 and 30 years of age inclusive can be approximated by the equation or functionN(a)=2a^2-80a+5000where a= age of driver.

Calculate n(20) and explain what this answer means.

What is the domain of this function?

Can this function be used to calculate the approximate number of accidents for people my grandfathers age (65 years)? why or why not?