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Graphene looks like it 's going to be one of the " wonder materials " of the future , and a science team at Cornell University have just demonstrated the world 's smallest balloon made of it .

How are the Cornell people able to make a balloon out of graphene ?
Available choices: i. Graphene is wonderful and you can do a lot with it .. ii. Graphene is just like latex , no chemical difference at all .. iii. Cornell is able to use trash to get rid of graphene .. iv. Cornell is lying , they did n't really do anything with graphene ..
i.