a) Calculate Kristina's commission for November

First, we need to calculate Kristina's total eligible sales for November. She made sales of $23,421, and the sales returns were $576. So, her net sales for November are:

$\text{Net Sales} = 23,421 - 576 = 22,845$

Now, we can calculate Kristina’s commission based on the three-tiered commission rate.

1. First tier: 2.3% on sales up to $3,800
   The commission on the first $3,800 is:

$\text{Commission on first } 3,800 = 3,800 \times \frac{2.3}{100} = 87.40$

2. Second tier: 4% on the next $5,100
   Kristina’s sales exceed $3,800, so the next $5,100 will be subject to the 4% commission rate. The commission on the second $5,100 is:

$\text{Commission on next } 5,100 = 5,100 \times \frac{4}{100} = 204$

3. Third tier: 10.1% on the remaining sales
   After the first $3,800 and $5,100, the remaining sales are:

$\text{Remaining Sales} = 22,845 - 3,800 - 5,100 = 14,945$

The commission on these remaining sales is:

$\text{Commission on remaining sales} = 14,945 \times \frac{10.1}{100} = 1,511.20$

Now, we add up the commissions from each tier:

$\text{Total Commission} = 87.40 + 204 + 1,511.20 = 1,802.60$

So, Kristina’s commission for November is $1,802.60.

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b) Calculate her average hourly rate

To calculate her average hourly rate, we use the total commission and divide it by the number of hours she worked in November.

$\text{Average Hourly Rate} = \frac{\text{Total Commission}}{\text{Hours Worked}} = \frac{1,802.60}{32} = 56.38$

So, Kristina's average hourly rate for November is $56.38.

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Would you like any further details on the calculations or concepts used? Here are some related questions to explore:

1. How would Kristina's commission change if her sales were higher than $23,421?
2. How do tiered commission rates differ from flat commission rates in terms of income potential?
3. How do commission structures impact employee motivation in sales?
4. What are the pros and cons of commission-based pay versus salary-based pay?
5. How would Kristina’s commission look if she had $0 in returns?

Tip: When calculating commissions, always break down the sales into the different brackets specified by the commission structure to avoid missing out on any higher-rate commissions.