Treat the ottoman as a cylinder.
area of the top surface is πr²=π*16²
The total lateral area (the side) is: π*d*h=2*16*π*(6+8)=28*16π (diameter is twice the radius, so d=2*16)
the area of the green part is: π*d*8=2*16**8π=16*16π
not including the bottom, the total area is the top plus the total side:16²π+16*28π=(16+28)*16π=44*16π
the percent of the green part is: 16²π/44*16π=16/44≈36%
Is 36% a choice?