# How can I calculate probability of the waiting time in an M/G/1 queue?

Let $$W$$ denote the waiting time in an M/G/1 queue with customers arriving according to a Poisson Process and service times i.i.d with distribution $$F(t)$$.

How can I calculate $$\mathbb{P}(W>0)$$ and $$\mathbb{P}(W>1)$$?