$($All answers were generated using $1,000$ trials and native Excel functionality.$)$

like to use a simulation model to analyze this situation.

$($a$)$ What is the average monthly profit resulting from its policy of stocking $260$ pairs of goggles at the beginning of each month? Round your answer to the nearest dollar.

$($b$)$ What is the proportion of months in which demand is completely satisfied? Round your answer to the nearest whole number.

$\%$

answer to the nearest dollar.

The average difference between the net profit generated by a replenishment level of $280$ versus a replenishment level of $260$ is $

W$.$ It means that monthly replenishment level of

increases profitability.