Which characteristic is correct for the function f(x)=−2x4+3x2 ?

Regular selling price (price before discount) 100%.

Price after trade discount of 15% is 85% of regular selling price..

Price after trade discount reduced to 10% is 90% of regular selling price.

By reducing the trade discount from 15% to 10% meant increasing the selling price by 5% of the selling price before applying the trade discount.