The circle x² + y² + 4x $$-$$ 7y + 12 = 0, cuts an intercept on Y-axis equal to

In a circle of diameter 44 cm, the length of a chord is 22 cm. What is the length of minor arc of the chord?

The circle $ x ^ 2 + y ^ 2 - 2kx - 2ky + k ^ 2 = 0$ touches the x-axis at P and y-axis at Q. What is PQ equal to?

What is the equation of the circle whose diameter is 10 cm and the equations of two of its diameters are $x+y=0$ and $x-y=0$?