Gorter and grendel extracted lipids from human red blood cells. they calculated the total surface area for these red blood cells and found it to be 36 µ2. how much surface area would these lipids cover once they were spread across the surface of water?

The calculated to surface area for red blood cells by Gorter and Grendel found to be 36u2.

 The surface area that would be covered once they spread across the surface of the water is 72u2.

If they spread across the surface area will double. This is because the lipid bilayer with phospholipid the head faces the water on each surface of the membrane.
 It clearly shows that there must be more to membranes than lipid bilayer because membranes grew and the surface tension of membranes is much lower than those of pure lipid structures.

Resistance than a bicycle? i'm not entirely sure

Ithink the answer is d.