**1. The problem statement, all variables and given/known data**

http://postimg.org/image/d4z88fehh/

http://postimg.org/image/d4z88fehh/

**2. Relevant equations**

http://postimg.org/image/kfkcgs6mr/

**3. The attempt at a solution**

I got this one equation, but I have to simulate this model and I need one more to suceed it.

I got this one equation, but I have to simulate this model and I need one more to suceed it.