A bag contains 4 red marbles and 8 white marbles. A marble is picked and replaced. What is the probability you picked a white and then a red marble?

Last month, leonhard euler's watch kiosk at the mall had total sales of $9,489. merchandise totaling $225 was returned. the goods that were sold cost leonhard euler's $5,481. operating expenses for the moth were $992. what was the gross profit on sales?