For the last part of this lesson, I've just set out these little exercises using the key of G. These lessons were all created with of tempo of 80 - not a bad tempo to start off on. Once it's comfortable, speed it up.

On a side note, double stops (like anything) can just get to the point of sounding boring. Don't do them all the time - they're an ornamentation. Get comfortable with them, be confident in where you need to go when you want to throw one of them out and use them tastefully or in solos. The less you use them, the more people will say, "Wow!, that sounded cool...whatever it was they were doing on the bass! I want to give them large sums of money!"

Hope this lesson was useful to you. Have fun.