15) What are the entry requirements for the United States of America?

If your stay is 90 days or less, you may be eligible for the Visa Waiver Program. And, you can apply for an Electronic System for Travel Authorisation (ESTA) online through our travel partners - Sherpa 
For full details on the Visa Waiver Program, and up to date travel advice for the USA, please visit the Foreign Office website https://www.gov.uk/government/publications/visas-and-travel-requirements.
From April 1st 2016, all visitors to the USA must have an electronic biometric passport, also known as an e-passport, to qualify for visa-free entry under the Visa Waiver Programme.