Answer:

Step-by-step explanation:
Since there 3600 seconds in an hour, and because you are going from a smaller unit to a bigger unit, you divide 68 by 3600 to get this:
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0,018
The "8" tells the hundredths digit to round up one, so you approximately get 0,02.
* That bar over the "8" tells you that it repeats.
I am joyous to assist you anytime.