If the diagonals of a square ABCD intersect each other at O, then △OAB is

1. an equilateral triangle

2. a right angled but not an isosceles triangle

3. an isosceles but not right angles triangle

4. an isosceles right angled triangle.

The diagonals AC and BD of a parallelogram ABCD intersect each other at the point O. If ∠DAC = 32° and ∠AOB = 70°, then ∠DBC is equal to

1. 24°

2. 86°

3. 38°

4. 32°

If PQRS is a parallelogram, then ∠Q - ∠S is equal to

1. 90°

2. 120°

3. 0°

4. 180°

A diagonal of a rectangle is inclined to one side of the rectangle at 25°. The acute angle between the diagonals is

1. 55°

2. 50°

3. 40°

4. 25°