Assuming you're running Windows, click the start button, and then search for "Device Manager" (or open CMD or PowerShell and type devmgmt.msc). Look at the list of devices. If Bluetooth is there, you have it; if it's not there, you don't.
c) open
I think this because when you're in an open space (such as starbucks) it's public for anyone to enter. I think.
Answer:
1. It has a clear objective.
2. It's useful to your audience.
3. It's well-rehearsed.
4. Your presentation deck uses as little text as possible.
5. Your contact information is clearly featured.
6. It includes a call-to-action.
Explanation: