What can be measured in nanometers?

Nanometers are a really small measurement, one billionth of a meter, I believe.

So nanometers is used to describe tiny stuff, like atoms of a water molecule, and waves of  light.

the given 6 = w/p is equivalent to 6p = w, where w is the total area of the walls and p is the area covered by a single can of paint.

knowing that 6 cans of paint will be needed, 6p = w becomes 6(6) = w = 36.   this tells us that the total area to be painted is 36 square units.