Based on the standards of units conversion, to convert from micrometer to meter, we multiply by 10^-6.
Since we there is a square (10^2) to consider, then to convert from micrometer squared to meter squared, we will multiply by (10^-6)^2 as follows:
1.5 μm2 = 1.5 x (10^-6)^2 = 1.5 x 10^-12 meter sqaures
