Answer:
Forces affect how objects move. They may cause motion; they may also slow, stop, or change the direction of motion of an object that is already moving. Since force cause changes in the speed or direction of an object, we can say that forces cause changes in velocity.
This one is also using pre-conventional moral reasoning.
Answer:
Our answer is D
Explanation:
Efficiency = Work Done/Heat Input = 80/80 = 1
So Option D....The efficiency of this engine is greater than the ideal Carnot cycle efficiency
Answer:

Explanation:
It is given that,
The coordinates of a particle in the metric xy-plane are differentiable functions of time t are given by :


Let D is the distance from the origin. It is given by :

Differentiate above equation wrt t as:

.............(1)
The points are given as, (12,5). Calculating D from these points as :

Put all values in equation (1) as :


So, the particle is moving away from the origin at the rate of 7.076 m/s. Hence, this is the required solution.