The latitude of Jackson, Mississippi is 32degrees17minutes N, and the latitude of St. Louis, Missouri, is 38degrees37minutes N. The radius of Earth is about 4000 miles.

a) About how far apart are the two cities?

b) If Earth makes one revolution every 24 hours, what is the linear velocity of a point near the equator?

Having severe trouble over here. For a) I know the difference of their latitudes is 6degrees20minutes but I don't know what to do from there.

And for b) I did (4000)(2pi/24). I don't know if it's right though.