THIS IS NOT THE ANSWER, IT'S AN EXAMPLE!!
(You didn't show the numbers that were given for me to answer this. BUT in the example, it shows you how to solve it. Just replace the numbers I put with the ones you were given. If you want me to solve it still, please comment the numbers on this for the answer)
Example; First, write the formula.
A=bh
Next, substitute in the values you have been given.
A=6×2
Then, do the multiplication.
A=12
The answer is 12 sq. cm.