Answer:
W = -1400 J
Explanation:
Let's use the relationship between work and kinetic energy
W = ΔK
kinetic energy is
K = ½ m v²
therefore in this case
K₀ = 1400 J
Thus
W = 0 -1400
W = -1400 J
The negative sign indicates that the work is done against the energy, that is, in the opposite direction to the movement
