Cammie buys a new hockey stick at the monkey sports mega store . The price listed on the stick was $120. When she paid for the stick at the register the total cost , including the sales tax, was $129.60. What was the sales tax rate that cammie was charged?

1. 8.5%

2. $9.60

3. 8 %

4. 7.5%

5. $129.60