I really need help with this conversion problem. Oil spreads in a thin layer on water called an ';oil slick ';.?

How much area in m^2 will 200 cm^3 of oil cover if it forms a layer 0.5 nm thick? The answer is 4x 10^5, I want to know the steps to solving this problem to come up with that answer. Please show me how to solve this problem and thank you so much for your help!I really need help with this conversion problem. Oil spreads in a thin layer on water called an ';oil slick ';.?
First you convert volume of oil to m^3: (1 m^3 = 10^6 cm^3)


200cm^3 * (1m^3/10^6 cm^3) = 2*10^-4 m^3





Then, know that 1 nm = 10^-9 m, and divide the volume by the thickness, both in m^3:


2*10^-4 / 0.5*10^9 = 4*10^5 m^2