Final Answer:
The correct answer is graphs included, Time taken: 8 seconds, Distance traveled: 80 meters, thus the correct option is A.
Step-by-step explanation:
Acceleration is defined as the rate of change in velocity over a given period of time. In this problem, the given velocity is +20 m/s, which means that the object is moving in the positive direction. The time taken to reach the speed of +20 m/s is 4 seconds, and the object stays at the given velocity for another 4 seconds. The total time taken is 8 seconds.
Using kinematics, the distance travelled can be calculated using the equation: s = ut + (1/2)at2, where s is the distance, u is the initial velocity, t is the time taken and a is the acceleration. In this case, the initial velocity is 0 m/s since the object is at rest, the time taken is 8 seconds and the acceleration is 2.5 m/s2 (20/8). Substituting these values into the equation, the distance travelled can be calculated as 80 meters.
The 3 graphs for this problem can be drawn as follows:
The velocity-time graph shows the increase in velocity of the object from 0 m/s to 20 m/s in 4 seconds, followed by a constant velocity of 20 m/s for the next 4 seconds.
The acceleration-time graph shows the constant acceleration of 2.5 m/s2 over the 8 second period.
The distance-time graph shows the total distance travelled by the object over the 8 second period, which is 80 meters.