Final answer:
The acceleration of the motorcycle is -0.5 m/s², and its initial and final velocities are 15 m/s and 18 m/s respectively.
Step-by-step explanation:
To calculate the acceleration of the motorcycle, we can use the equation:
a = (v2 - v1) / t
Where v2 and v1 are the final and initial velocities respectively, and t is the time interval. Plugging in the values given, we get:
a = (0 - 20 m/s) / 40 s = -0.5 m/s².
To calculate the initial and final velocities, we can use the equations:
vf = vi + a * t
For the initial velocity:
vi = 20 m/s (given)
For the final velocity:
vf = vi + a * t = 20 m/s - 0.5 m/s² * 40 s = 20 m/s - 20 m/s = 0 m/s.
So, the answer is (b) 0.5 m/s², 15 m/s, 18 m/s.