Answer:
The average velocity is 180 km/hr
Explanation:
Given;
initial velocity, u = 60 km per hour
final velocity, v = 120 km per hour
initial time = 1 hour
final time = 2 hour
Initial position = 60 km/h x 1 hour = 60 km
final position = 120 km/h x 2 hour = 240 km
The average velocity is given by;

Therefore, the average velocity is 180 km/hr
"2 km/hr/s" means that in each second, its engines can increase its speed by 2 km/hr.
If it keeps doing that for 30 seconds, its speed has increased by 60 km/hr.
On top of the initial speed of 20 km/hr, that's 80 km/hr at the end of the 30 seconds.
This whole discussion is of <em>speed</em>, not velocity. Surely, in high school physics,
you've learned the difference by now. There's no information in the question that
says anything about the train's <em>direction</em>, and it was wrong to mention velocity in
the question. This whole thing could have been taking place on a curved section
of track. If that were the case, it would have taken a team of ace engineers, cranking
their Curtas, to describe what was happening to the velocity. Better to just stick with
speed.
Answer: B. Its randomness would increase
Explanation:
According to the <u>second law of thermodynamics</u>:
<em>"The amount of entropy in the universe tends to increase over time"</em>
<em />
That is, in any cyclic process, entropy will increase, or remain the same.
So, in this context, entropy is a thermodynamic quantity defined as a criterion to predict the evolution or transformation of thermodynamic systems. In addition, it is used to measure the degree of organization of a system.
In other words: Entropy is the measure of the disorder (or randomness) of a system and is a function of state.
39 % might be the answer ..
hope it helped