We can figure this out by finding the seconds in an hour, then multiplying it by 0.8 to give us the amount of seconds in 0.8 hours.
There are 60 minutes in an hour, and 60 seconds in a minute. Therefore, there are 60*60 seconds in an hour, which gives us 3600. Multiplying that by 0.8 gives us 2880 seconds in 0.8 hours.
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