Answer:
1 cm^2 : 9 m^2
Step-by-step explanation:
The scale factor of an area is the square of the scale factor of a length.
The scale for lengths is 1 cm : 3 m.
You now square that scale to get the scale of the areas.
Scale of areas:
(1 cm)^2 : (3 m)^2
1 cm^2 : 9 m^2
