For diffusion to occur, which condition must be met?

Natalie had random hand movements when she was two months old. when she was six months old, she used to grab a block with her whole hand. now at the age of ten months, she can grasp the same block with her thumb and forefinger. this sequence of growth in her hand and finger movements is according to the pattern.

What’s this animal (picture is tagged) and where is it most likely to live, rainforest or desert?

Which layer will become saturated first when rain falls?