Good question!
The image transmitted by the lens is actually circular, but it passes through a rectangular opening just before the film plane. This creates a rectangular image on the film because part of what the lens is transmitting is blocked. You are never reminded of this since the entire "previewing" system is constructed to show you what you will get, not what the lens actually "sees".
The square footage of a circle that measures 159 feet in circumference is about 2,012 square feet.
Pxr2
Area of a circle = pi*radius2
If you mean a circle then its square footage formula is: pi*radius2
The square footage of a radius is meaningless, but if you mean the square footage of a circle of radius say R, the answer is 3.142 x R x R
10,354.9 square feet.
7850
490.87
Area of a circle = pi*radius2 measured in square feet
Area of a circle = pi*radius2
Area of a circle = pi*radius2
Area of a circle is pi*radius^2. So if the radius is measured in feet, the area (or the square footage) of a half circle is: (pi*r^2)/2