Question

Please help, seriously struggling to understand:
Calculate the surface area of the dishwashing circle to molecules per layer (this requires converting the surface area from meters to nanometers):
17.5cm^2 * 1m^2 * 1 * 10^18 * 1 = __molecules
Top layer
surface area 10,000cm^2 * 1m^2 * 0.210nm^2 = __top layer