How could you increase the rolling friction between the car and track? how could you decrease it?

If you touch a hot light bulb and get burned, that is an example of a. radiation b. convection c. conduction

Looking at this barometer, is the air pressure high or low? what type of weather would you expect? high, bad low, bad high, good low, good

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.