Shopping in St Louis

The tax for this mug from St Louis is 10.991% (what a strange value but that is what it is). The price tag (which excludes tax) for this mug is $9.95.

What is the amount (including tax) that one has to pay for this mug?

This is in US Dollars.

Does a Starbucks mug cost more or less than it is in St Louis?

Cathedral Basilica of Saint Louis