Answer:
The correct answer is option b.
Explanation:
In velocity vs time graph, vertical axis represent velocity vector and horizontal axis represents time. The slope of the line obtained in this graph is equal to the acceleration.

- If the line is straight makes an acute angle with horizontal axis then it is considered as positive acceleration.
- If the line is straight makes an obtuse angle with horizontal axis then it is considered as negative acceleration or deceleration.
conservation of momentum ... that before = that after ... change zero
Answer:
the answer is 30 Ohms. Not found in the options provided
The force he must exert is 300 N