The highest-earning method is the monthly salary of $3000 plus 2% commission on all sales.
Option B shows the correct method for most earnings.
A commission is a percentage of total sales as determined by the rate of commission.
Given that the monthly sale is $73620. We need to calculate the money earned in each method to determine the best method to pay most earnings.
A: Straight commission of 6% on all sales.
Commission = [tex]\dfrac {6}{100} \times \$73620[/tex]
Commission = $4417.2
Money earned = $4417.2
B: Monthly salary of $3,000 plus 2% commission on all sales.
Commission = [tex]\dfrac {2}{100} \times \$73620[/tex]
Commission = $1472.4
Money earned = $ 3000 + $1472.4
Money earned = $4472.4
C: Graduated commission of 4% on the first $50,000 in sales and 9% on anything over that.
Commission = [tex]\dfrac {4}{100} \times \$50000 + \dfrac {9}{100} \times \$23620[/tex]
Commission = $4125.8
Money earned = $4125.8
D: Graduated commission of 5% on the first $35,000 in sales and 7% on anything over that.
Commission = [tex]\dfrac {5}{100} \times \$35000 + \dfrac {7}{100} \times \$38620[/tex]
Commission = $4453.4
Money earned = $4453.4
Hence we can conclude that the highest-earning method is the monthly salary of $3000 plus 2% commission on all sales.
To know more about the commission, follow the link given below.
https://brainly.com/question/929522.