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There are four cards placed on a table:

4 cards

You’re told that each of the four cards has a numeral on one side and a letter of the alphabet on the reverse side. You’re then asked to prove that the following statement is either true or false:

If a card shows an even number on one side, then the other side is a vowel.

You are allowed to turn over two cards. Which cards should you turn over?

On 20. March 2015 a total solar eclipse was visible in the area between Iceland, Scottland and the Faröe Islands up to the North Pole. Eclipse Flight AB1234 from Düsseldorf to Düsseldorf flew through the umbra near the maximum eclipse point at an altitude of 35000 ft.