The sum of the interior angles of a quadrilateral is _____?

270°

360°

180°

None of these

Using the formula for the sum of interior angles of a polygon:

(n - 2) × 180°

For a quadrilateral, n = 4:

(4 - 2) × 180°

= 2 × 180°

= 360°

The sum of the interior angles of a quadrilateral is 360°.