For this problem, we are given a rectangle and its dimensions. We need to use this information to determine the area of the rectangle.
The rectangle's area is given by the following expression:
[tex]A=(\text{width)}\cdot(\text{length)}[/tex]For this problem, we have:
[tex]A=9\cdot30=270\text{ square milimiters}[/tex]The rectangle's area is 270 square milimiters