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i)Region A – shows ice becoming warm from below 00C.
B – shows that the temperature remains 00C as all the ice melts
C – shows water becoming hotter from 00C to 1000C when it begins to boil.
D – shows water boiling and the temperature remains constant.
ii)In B and D regions, the heat supplied is being used to bring about the change in structure from one physical state to another and so the temperature does not rise.
Kavungya answered the question on March 25, 2019 at 08:06
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(i) Oily and greasy –
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