Answer:
Because they are hydrophobic
Step-by-step explanation:
The image shows a cell membrane, which is made up a phospholipid bilayer. The phospholipid bilayer is made up of a phosphate head, which is hydrophillic, and fatty acid tail, which is hydrophobic. That means they are repelled by water.
Because the tails are hydrophobic, they are repelled by the water towards one another, while the heads remain facing outwards,