The organs are known as Vestigial organs. The evolution from land-dwelling animal to the marine animals has led whales as well as dolphins, to lose hind limbs. The pelvic and leg bone serves no purpose in them and just provide the anchorage to muscles
Ans: Cells are so small because it allows them to have a better surface area to volume ratio. This makes it much easier for the cell to bring in necessary nutreints and excrete wastes. Also the smaller the cell is, the less time it takes to replicate the small cell as opposed to a bigger cell.
C. employment and unemployment
because it is the only one that makes sense
The black box because black reflects more heat than white