Thanks to who can help, I will thumb up

On March 10, Sugimoto Household Goods sells 2,000 boxes of toothpaste to Wong DDS for $6,000. Sugimoto's cost is $1 per box. Payment terms are 1/5,n/30. Shipping terms are FOB Destination. On March 13, Wong returns 100 boxes of toothpaste because it does not have tamper proof packaging. Sugimoto cannot resell this toothpaste and must scrap it (throw it away). On March 14 Wong realizes that the toothpaste they received does not have the Disney characters on the packaging. They specifically ordered the Disney characters for their pediatric patients. Wong contacts Sugimoto, who agrees to give them a $800 allowance. Wong agrees to keep the toothpaste to give away to their adult patients. On March 20, Wong pays Sugimoto the outstanding balance, less any applicable discounts. How much does Wong pay Sugimoto? How much of a discount is Wong allowed to take