Castel left the science museum and traveled toward the mountains. Sumalee left one hour later traveling 10 km/h faster in an effort to catch up to him. After two hours Sumalee finally caught up. What was Castel's average speed? Show your work.

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.