Square Feet. The square foot is a unit of area used in the imperial and U.S. customary measurement systems. A square measurement is the two-dimensional derivative of a linear measure, so a square foot is defined as the area of a square with sides 1 ft in length.
http://wiki.answers.com/Q/How_long_is_a_black_rhino_pregnant_for. A Black Rhino is pregnant usually between 419 and 478 days, or 15 to 16 months. The mother will give birth to a single calf, weighing in on average 35 to 50 kg, (about 80 pounds). The calf will stay with it's mother anywhere from 2 to 3 yea...
Male elephants are called bulls and females are called cows. After mating, the cow will be pregnant for around 22 months. When the baby elephant is finally born, it can weigh around 200 lbs. (91 kg) and stand about 3 feet (1 m) tall. A baby elephant is called a calf. As the calf grows, it will gain 2 to 3 lbs. every day until its first birthday.