If you are asking what the total cost of the ring, including tax and shipping charges, will be, then you need to calculate the sales tax, excise tax, and then add those along with the shipping fee to the price of the ring.
What is 6% of 7200?
6% = 0.06
0.06 * 7200 = 432
What is 10% of 7200?
0.10 * 720 = 720
The total cost of the ring will be 7200 + 30 + 432 + 720 = $8,382