The formula for kinetic energy is

. Thus, the equation for velocity is

.
The work done is the product between the intensity of the force applied F, the amount of the displacement d of the book and the cosine of the angle

between the direction of the force and the direction of the displacement:

In our problem, the student is lifting the book, so he is applying a force directed upward, and the book is moving upward, so F and d are parallel and therefore the angle is zero, so

Therefore, the work done is
Answer: 0.016 h
Explanation:

It is given that, biker has an average speed = 18 km/h
Total distance traveled = 0.30 km
Therefore, time taken by biker to travel this distance:

Thus, the biker takes 0.016 hours to travel the segment of 0.30 km at an average speed of 18 km/h.
Answer: (1) The resistance increases and the current decreases.
Explanation:
When the temperature of the filament increases, the vibrational energy of the constituent atoms increases which leads to increase in inter-atomic collision. Thus, the resistance would increase. The increases in resistance would obstruct the flow of charges more leading to decrease in the value of the current.
Hence, when the temperature of the filament increase, the resistance increases and current decreases.