Let PQ be a diameter of the circle x² + y² = 9. If $$\alpha $$ and $$\beta $$ are the lengths of the perpendiculars from P and Q on the straight line,
x + y = 2 respectively, then the maximum value of $$\alpha\beta $$ is _____.

The diameter of the circle, whose centre lies on the line x + y = 2 in the first quadrant and which touches both the lines x = 3 and y = 2, is _______ .

The number of integral values of k for which the line, 3x + 4y = k intersects the circle,
x² + y² – 2x – 4y + 4 = 0 at two distinct points is ______.

If the curves, x² – 6x + y² + 8 = 0 and
x² – 8y + y² + 16 – k = 0, (k > 0) touch each other at a point, then the largest value of k is ______.