The annual commissions earned bu sales representative of Machine Products, a manufacturer of light machinery, follow the normal distribution. The mean yearly amount earned is $40,000 and the standard deviation is %5,000

The sales manager wants to award the sales representatives who earn the largest commissions a bonus of $1,000. He can award a bonus to 20% of the representatives. What is the cutoff point between those who earns a bonus and those who don't?