Which of the following do you suggest for Sid to pick to score a centum in his exam?
 
1.
Statement 1: The process of boiling vegetables can be reversed.
 
Statement 2: Burning paper turns into ash.
 
 
2.
Statement 1: When food gets spoiled, it produces a foul smell is an irreversible change.
 
Statement 2: A slice of an apple acquires a brown colour, if it is not consumed immediately is a physical change.