Final answer:
To calculate the total cost of the watch with sales tax and excise tax, multiply the retail price by the respective tax rates and add them together.
Step-by-step explanation:
To calculate the total cost of the watch with sales tax and excise tax, first find the amount of sales tax by multiplying the retail price by the sales tax rate of 6%. Then, find the excise tax amount by multiplying the retail price by the excise tax rate of 10%. Finally, add the retail price, sales tax amount, and excise tax amount together to find the total cost of the watch.
Let's calculate:
The sales tax amount = $8000 * 0.06 = $480
The excise tax amount = $8000 * 0.10 = $800
The total cost of the watch = $8000 + $480 + $800 = $9280.