Answer:
300 N
Explanation:
We have three forces acting on the object:
- W = 1500 N, downward: the weight of the object
- F1 = 1200 N, upward: the force exerted by the first man
- F2, upward: the force exerted by the friend
In order to lift the object, the sum of the two forces F1 and F2 must be at least equal to the weight of the object W. Therefore we can write

And from this equation, we can find the magnitude of F2:

Answer: a = 1, b = 9, c = 6, d = 4
Explanation:
With no velocity, total mechanical energy is all gravity potential energy
PE = mgh = 80.0(9.81)(25) = 19,620 J = 1.96e4 J
Sorry but i dont know i was doing this for some point sorry
Answer:
c) those caused by parasites