**difficulty:** easy **type:** mcq **focus:** focal-distance-formula For P(x1, y1) on x^2/25 + y^2/16 = 1 with focus S(3, 0), SP equals:

**difficulty:** medium **type:** mcq **focus:** minimum-focal-chord The minimum length of a focal chord of x^2/25 + y^2/16 = 1 is:

**difficulty:** medium **type:** mcq **focus:** conjugate-diameters Two diameters y = m1*x and y = m2*x of x^2/16 + y^2/9 = 1 are conjugate if:

**difficulty:** medium **type:** mcq **focus:** auxiliary-circle A point P on x^2/25 + y^2/9 = 1 has eccentric angle pi/3. The corresponding point Q on the auxiliary circle is:

**difficulty:** easy **type:** mcq **focus:** focal-distance-sum If P is any point on x^2/25 + y^2/9 = 1 with foci S and S', then SP + SP' equals: