Coountry field in Billing info & Shipping Info

After I install the MarketPress plugin, I notice the following 2 sections were added to the WordPress Profile page for each user: Billing Info and Shipping Info. There is a Country field with United State and Canada as the only two options.

Please find my questions on the screenshot blow. Thank you!

Q1. How to add the full country list as the drop down options?

Q2. How to set the default coutry showing up as the default option?