7 A circle with centre \(C ( - 3,2 )\) has equation
$$x ^ { 2 } + y ^ { 2 } + 6 x - 4 y = 12$$
- Find the \(y\)-coordinates of the points where the circle crosses the \(y\)-axis.
- Find the radius of the circle.
- The point \(P ( 2,5 )\) lies outside the circle.
- Find the length of \(C P\), giving your answer in the form \(\sqrt { n }\), where \(n\) is an integer.
- The point \(Q\) lies on the circle so that \(P Q\) is a tangent to the circle. Find the length of \(P Q\).