Researchers have concluded that a dry basin began to fill with water in 1880. the water level rose an average of 1.6 millimeters (mm) per year from 1880 to 2009. the rise in water level since 1880 can be modeled by f(x) = 1.6x, where x is the number of years since 1880 and f is the total rise of the water level in mm.

1. what is the domain of f(x)?
2. by how much did the water level rise in all from 1880 to 1950?
3. in what year was the water level 100 mm higher than in 1880?

remember: 1 m = 1,000 mm

and