Answer to Question 1
Phospholipids are amphipathicthey contain both nonpolar and polar portions. In this way, phospholipids can interact with water or other hydrophilic substances on their polar end and hydrophobic substances such as lipids on the other end (fatty acid portion). They can form a bilayer that acts as a barrier between the inside and outside of the cell (because of the hydrophobic interior) but still allows communication between the inside and outside (because of the hydrophilic exterior).
Answer to Question 2
c