Because chemical changes<span> produce new substances, they often cannot be undone.</span><span> </span>Some chemical changes can<span> be </span>reversed<span>, but only by other </span>chemical changes<span>.
Hopefully this helps!</span>
the truck that's parked because it has more mass
D. A heat pump being 80%efficient
200 newton meters is put over the distance of 20 meters, then over the distance of 10 meters 100 newton-meters must be put (simple fraction over 2).
At the same distance of 10 meters but during lifting you need to put 150 newton-meters (which means 50Nm more than during horizontal movement).
According to that you can say that the machine's advantage is horizontal movement because it does smaller work than during lifting objects. That means it consumes then less energy and then it costs less.