Answer:
D
Step-by-step explanation:
A: Velocity has direction. Once the car changes direction, the velocity is no longer a constant.
B: The direction makes B untrue
C: r = 40 miles / 2/3 hour = 60 miles/hour
r2 = 30 miles / 1/2 hour = 60 miles / hour
The car is not decreasing its speed. C is false.
D: Speed does not have a direction. D is true.