A Polish national is REQUIRED to have a visa to enter the U.S. So, without a visa, a Polish citizen cant enter the US at all- period (never mind how long he can stay).
6 months
A US citizen can stay in Malaysia for up to 90 days without a visa.
As a US citizen, you can stay in Germany for up to 90 days within a 180-day period without a visa.
Forever, don't get caught though.
A Japanese citizen can stay in the Philippines for up to 30 days without a visa. If they wish to stay longer, they will need to apply for a visa extension through the Philippine Bureau of Immigration.
A US citizen can stay in Japan for up to 90 days without a visa for tourism or business purposes. If they wish to stay longer, they would need to apply for a visa or an extension of stay.
Yes, as long as you hold a passport.http://travel.state.gov/visa/visa_1750.html
That depends on their visa.
Not a travelling Visa as long as you are a US citizen. If you mean a Visa Credit Card, then I would assume not.
An American can stay in Italy for up to 90 days within a 180-day period without needing a visa or residency permit. After 90 days, they would need to obtain a visa or residency permit to stay longer.
As long as your visa is valid