Hi Ivan,
We have a couple responses for you:

Hello
As soon as you see square centimeters, you know to think "area". The formula for area of a rectangle is
A = Length X Width.
The length of your rectangle here is 210 cm and the width of your rectangle is 39 cm. If you multiply those two numbers together you will find the "area" or how many square centimeters.
Karen McIver

Hi Ivan,
Square centimeters is a term we use when stating the area of something.
If you are being asked how many square centimeters are in something, you are
being asked what is the area of the object.
Recall that in a rectangle:
A = L * W
In your question you are given length and width. Your units for your answer
will be written in cm^{2} (or centimeters squared).
(You can also remember squared as multiplying '2' numbers together, ie.
squared)
Mel
