Answer:
72 square units
Step-by-step explanation:
The figure shown has a uniform horizontal cross section, so is equivalent to a rectangle with length 12 and height 6. Its area is given by the rectangle formula:
A = LW
A = (12)(6) = 72 . . . . square units
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Additional comment
Essentially, the semicircle removed from the left side is tacked onto the right side. The rectangle area is unchanged by that.
