The answer depends on the units used for "twelve by twelve". It should be pretty obvious that the number of square feet in 12 micrometres by 12 micrometres will be different to those in 12 miles by 12 miles!
Since a 12" x 12" tile is exactly one square foot, the answer should be obvious.
12 square feet = 1.33333333... square yeards
12 (square feet) = 1.33333333 square yards
12 square km is equal to 4.63323 square miles.
12 feet times 12 feet = 144 square feet
Area = 12*12 = 144 square feet
144 square meters
12 square miles = 7,680 acres.
There are: 12 times 12 = 144 square feet
Answer: 12 m² = 129.166 ft²
12 square feet = 0.000275482094 acres.