Engineering 101 - How to find voltage?

[Mohdoo]

Homework Statement

The part that I am having problems with is part A, which asks for Is and Vl. I plain and simply can not figure it out. The teach provides answers to check our work, and she said Vl = 11.90 volts. But I don't see how that is the case. I also have no idea how to find Is :(

Homework Equations

I don't know :(

The Attempt at a Solution

I tried using equations to find the change in voltage over a resistor and then use that to find the voltage...Just plain didn't work :(

 

[miqbal]

Are you familiar with Kirchhoff's Laws?