Answer:
a)
& 
b) 
c) 
Explanation:
Given:
mass of the book, 
combined mass of the student and the skateboard, 
initial velocity of the book, 
angle of projection of the book from the horizontal, 
a)
velocity of the student before throwing the book:
Since the student is initially at rest and no net force acts on the student so it remains in rest according to the Newton's first law of motion.

where:
initial velocity of the student
velocity of the student after throwing the book:
Since the student applies a force on the book while throwing it and the student standing on the skate will an elastic collision like situation on throwing the book.

where:
final velcotiy of the student after throwing the book
b)



c)
Since there is no movement of the student in the vertical direction, so the total momentum transfer to the earth will be equal to the momentum of the book in vertical direction.



S=(0x4)+(0.5x4.81x4x4)
S=0.78.48
The depth is approximately 78 meters.
(My brain hurts now) :P Good Luck!
I think this is AWESOME, but I think the last sentence of your conclusion is a bit off. <span> "If someone has an allergy to oil then they can still eat cake because applesauce makes an amazing substitute for oil." I think that you should say "This recipe is great for those who cannot eat/drink oil, the applesauce is an amazing substitute for oil."
I hope I helped! -Wajiha</span>
<h2>Question:</h2>
An automobile is driving uphill. Which form of energy is not involved in this process?
<h2>Choosing:</h2>
electromagnetic
potential
kinetic
chemical
<h2>Answer:</h2>
<u>Electromagnetic</u><u> </u>
<h3>
<u>#READINGHELPSWITHLEARNING</u><u> </u></h3><h3>
<u>#CARRYONLEARNING</u><u> </u></h3><h3>
<u>#STUDYWELL</u><u> </u></h3>