Chapter 2 spelling and how to exit qemu?

Chapter 2 says You can exit the emulator using: <Ctrl-a x>. but the thing inside <> is not rendered because it is not escaped and looks like HTML tag to the markdown renderer so you need to view the raw text to see it otherwise it shows as You can exit the emulator using: ..

Also, what exactly do I need to press to exit qemu? I run the make run command via PuTTY in Windows and it loads fine but I am not able to stop it. I tried pressing Ctrl+A and then X or Ctrl+X and also Ctrl+A+X but it didn't work. What is this combo supposed to mean?