Question

kritika studied that all freely falling bodies must reach the ground simultaneously when drooped from a same height but she saw that if a crumbled paper and a plane paper sheet are dropped from the roof of a house the crumbled paper reach the ground first before reaching the ground of the plane paper sheet she got confused and ask her elder brother mahesh to explain the reason behind it

Answer 1

because crumble paper has less surface area
and less resistance in air no other force act on it rather than gf
on the other hand plane paper greater surface area and much resistance in air

Answer 2

because a plane paper has more area
than crumbled paper therefore a plane paper has more air resistant than the crumbled paper. crumbled paper falls first as it has less area .I.e. less air resistant.
this will help you