I don't understood one thing. So look at this test
2
00:00:00
00:00:00
In fact teakettle will be ready to 335.2 second. But if we round this answer, it will be 335, i.e. 00:05:35. And it seems that this correct answer. But to this time teakettle will not be ready!

And this test
3
00:00:00
00:00:00
00:05:35
And what should we think?
1) The teakettle is ready to 00:05:35, so in this time it will be EMPTY and the third student will BEGIN to boil water in this time 00:05:35?
So answer will be
00:05:35
00:05:35
00:08:23
2) Or we should think that in this situation teakettle will be ready EXACTLY in 335.2 second and the teakettle will be not empty and the third student just ADD water in 00:05:35?
So answer will be
00:08:23
00:08:23
00:08:23

My AC program says that you should think in the first way!))
The answer is
00:05:35
00:05:35
00:08:23
Good Luck!))

My AC program print
00:08:23
00:08:23
00:08:23

in time 00:05:35 temperature less than 100

Maybe both variants are right

No. Only the second answer is right. Thank you for good test :)

Thanks) AC)

Your tests are not correct.