The 'Assemble-It-Yourself' bookshelf product requires 12 glass panels for assembly. During the assembly process, customers often damage these glass panels, resulting in a shortage of panels to complete the product assembly. To address this issue, the seller has implemented a new policy of including an additional 4 glass panels in the product box at no extra cost. The probability of a glass panel being damaged during assembly is 0.15, and this probability remains constant and independent