A 40kg box sits on a shelf 0.5m above the floor. An employee moves the box to a height of 1.8m above the floor. How much work did the employee do in moving the box? A)20J B)72J C)200J D)520J E)720J

I'm thinking it's 2 you are asked to explain the earth's magnetic field. which is the best reply? 1. the earth's magnetic south is similar to the north pole of a magnet. 2. the earth's core has a strong magnetic charge similar to the south pole of a magnet. 3. the earth's geomagnetic south is similar to the south pole of a magnet. 4. the earth's magnetic charge is not centered at either pole; it varies based on location.