The line \(y=kx-5\), where \(k\) is a positive constant, is a tangent to the curve \(y=x^2+4x\) at the point \(A\).

(i) Find the exact value of \(k\).

(ii) Find the gradient of the normal to the curve at \(A\), giving your answer in the form \(a+b\sqrt5\), where \(a\) and \(b\) are constants.