How much feed would need to be supplied to a herd of 20 cattle, average weight 1000Kg, in order for them to increase their average weight to 1200Kg? Given the FCR of cattle is 5.0:1

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.