Answer:
245 km/h south
Explanation:
Since the motion of the car is a uniformly accelerated motion (=constant acceleration), we can use the following suvat equation:
[tex]v=u+at[/tex]
where
u is the initial velocity
a is the acceleration
t is the time
v is the final velocity
For the car in this problem we have:
[tex]u=85 km/h[/tex] is the initial velocity (taking south as positive direction)
[tex]a=4.0 km/h/s[/tex] is the acceleration (the direction is not specified; I assume it is south, so it is also positive)
t = 40 s is the time elapsed
Therefore, the final velocity is
[tex]v=u+at=85+(4.0)(40)=245 km/h[/tex]
And since the value is positive, the direction is south.
