Identify the coordinates of a point \(A\), where \(AB\) is the diameter of a circle whose centre is 3,-3 and \(B\) is \((7, 2)\). Also, find the radius of the circle.
 
The coordinates of point \(A\) \(=\)
 
The radius of the circle \(=\)
 unit
Answer variants:
5.4
6.4
4.9
1,-8
7.4
-1,-8
-1,8
1,8