Q. 123.7( 6 Votes )
Which of the following changes cannot be reversed?
(a) Blowing of a balloon
(b) Folding a paper to make a toy airplane
(c) Rolling a ball of dough to make roti
(d) Baking cake in an oven
(e) Drying a wet cloth
(f) Making biogas from cow dung
(g) Burning of a candle
(a) Can be reversed
(b) Can be reversed
(c) Can be reversed
(d) Cannot be reversed
(e) Can be reversed
(f) Cannot be reversed
(g) Cannot be reversed
Therefore, from the given options, the changes which cannot be reversed are (d), (f) and (g).
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