According to a recipe for purple paint, the ratio of milliliters of blue paint to milliliters of red paint in the mixture should be 20:4. Selena has 140 ml of blue paint. She wants to mix red paint to it to get the same shade as suggested by the recipe. For every 1 ml of red paint, the recipe suggests adding [Drop Down 1] of blue paint. So, for
140 ml of blue paint the amount of red paint needed is [Drop Down 2].