# Queueing server with exponential+deterministic stages

 P: 9 Hi, does anyone know how to model probability density function, b(x), of a system that has two parallel servers: -The first is selected by the customer with probability $p$, it has an exponential rate of $\mu$. -The second server is selected by the customer with probability $1-p$, it has a deterministic rate of $k$. -When a customer chooses a server, another servers waits until the customer being served leaves. If the second server were an exponential rate server, it would simply be an M/Er=2/1 system but now I don't know how to model this. Can anyone help me, plz?