A timer displays an alter after a fixed perious of time.
The two links illustrate different window styles.
Return to the index page fires the confirm method. This window displays 'OK' or 'CANCEL' 'OK' will take you back to the index page. 'CANCEL' leaves this pages displayed.
The VAT Calculator opens a prompt window for input. Enter say 100. A pop-up will then display the gross amount.

Open the index page in a new window?

VAT Calculator

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