If you had a freeway billboard, what would it say?

If I have a freeway billboard then I want to use as a speed limit in the busy highways which is beneficial in lowering accidents in our country.

Nowadays, millions of individuals killed due to accident especially in the highways due to fast speed. A large numbers of families are ruined due to these road accidents which kills a huge number of people.

So, if I have a freeway billboard then I want to install speed limits of vehicles that helps in reducing the number of accidents and thousands of lives are safe.