I have the following problem, im more comfortable when dealing with just normal or just gamma, but the NGa has thrown me.... anyone know how to do this?

An expert says her (prior) beliefs about μ and r can be summarised as:

(μ,r) ~ NGa(2.7, 1.08, 4, 0.2916)

How do i calculate the prior mean and standard deviation for μ and r?