Albert Einstein is experimenting with two unusual clocks which both have 24-hour displays. One clock goes at twice the normal speed. The other clock goes backwards, but at the normal speed. Both clocks show the correct time at 13:00.
What is the correct time when the displays on the blocks next agree?
Select one option, then click Submit.
05:00
09:00
13:00
17:00
21:00
Select an option, then submit.
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