How many centimeters are in a square that's area is 20 milometers?

Answer 1

This question cannot be answered because:

• there is no such unit as a milometre. Unfortunately, it could be a typo for either kilometre or millimetre - two measures which differ by a factor of a million!
• the area of a square cannot be either of these because both are 1-dimensional measures of length. Area is a 2-dimensional concept and according to basic rules of dimensional analysis conversion from one to the other is not valid.