a
(a)

\(y=\frac{4}{3 x^2+48 t^2+24 x t+2}\)

We need to convert it into the form of \(f(k x-\omega t)\)

\(y=\frac{4}{3\left(x^2+16 t^2+8 x\right)+2}\)

\(y=\frac{4}{3(x+4 t)^2+2}\)

\(v=\frac{\omega}{k}\)

Hence \(v=\frac{4}{1}=4 \,m / s\)