Explanation:
a. Average speed = distance / time
= 100 m / 70 s
= 1.43 m/s
b. Average displacement = displacement / time
= 0 m / 70 s
= 0 m/s
Distance is the length of the path traveled. Displacement is the difference between the final position and initial position.
Answer:

Explanation:
As we know by energy conservation
All its kinetic energy will convert into thermal energy to raise its temperature

now divide both sides by mass of the object

so change in temperature is given as



Hi! I'm a few days late since I just saw this question just now, but I'll answer anyway.
Answer:
When an unbalanced force acts on a moving object, the velocity of the object will change. Change in velocity means a change in speed, direction, or both. For example, if you kick a soccer ball and it moves from one place to another, it means that unbalanced forces are acting upon it. The ball moves from one place to another after kicking it so the position changed.