Write a question about the following article.

The prices represent Airmail rate to North America . Prices are subject to change without notice . No mimimum order via check , money order or credit card , but credit card orders under $ 15.00 will incur a $ 2.00 extra charge .

Question:
Why are the prices a bit high ?
Pick from:
[-] None of the above choices .
[-] It is for money orders .
[-] It is for shipping via air .
[-] It is for shipping to North America .