Mr. Cahn’s total earnings in a year is $18,900.
The total earnings is a function of the annual salary, commission and Christmas bonus.
Total earnings = annual salary + commission + Christmas bonus
Commission = 6% x (160,000 - 20,000)
6% x $140,000
0.06 x 140,000 = $8,400
Total earnings = $8,400 + 10,000 + $500 = $18,900
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