Thanks, I appreciate the welcoming!
And yes, I know exactly what you mean. This is what I told myself when I first read the question, thinking it was strange to neglect the change in diameter of the cable...I reread the question a couple times, and then realized that what the book really said...
1. A wire of a 6.0\Omega resistance is stretched to three times its original length. Assume the diameter and resistivity have stayed the same, what is its new resistance?
2. R=\stackrel{\rho L}{A}
3. Since the only thing that's changed in the equation is L, having tripled, I was...