At the top of a projectile's path above Earth, the acceleration of an object- A) goes from Negative to positive
B) is Zero
C)remains unchanged
D) goes from positive to negative

If your workout exceeds an hour you should substitute "a sports drink" for water.hope my answer has you : )

Ke reqd to move from 0 to 50 will be proportional to 50x50 or 2500. this is equal to w.  to change vel from 50 to 150 you need energy prop to 22500 - 2500 = 20,000. this corresponds to 8w.  best answer is a) . work reqd is prop to velocity squared. 

Do you still need with this

Number of electron i think