2*10^-23 / 1.66*10^-24
= 2/1.16 * 10^{-23--24)
= 2/1.16 * 10^{-23+24)
= 2/1.16 * 10^{1)
= 2/1.16 * 10
= 20/1.16
you can finish it
google it.
