It takes_ hours to reach the sea.
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Answer:
It takes 0.02 hours to reach the sea
Step-by-step explanation:
The answer is 0.02 hours because:
1) You have to divide 0.5 and 21
2) The answer would be: 0.0238095238
3) Now, round you answer to the nearest hundredth.
4) Your answer will be 0.02
Hope this helps!