The xiphoid process is the smallest and most inferior region of the sternum, or breastbone. At birth, it is a thin, roughly triangular region of cartilage that slowly ossifies into a bone and fuses with the body of the sternum.
City Blocks differ in size, but the typical square city block reaches 16 or 17 per mile, or 2.21 to 2.50 Acres. Engineers use a typical city block as 100,000 sq. ft. for calculation estimates, which is about 17 blocks per mile or 2 1/4 acres. (A football field is 300 feet by 160 feet, which is 1.1 Acres.)
On the Manhattan grid (i.e., generally above 4th St.), the rule of thumb is that 20 short blocks equal a mile. Short blocks are along avenues, going roughly north-south, from one (numbered) street to the next. A long block (along streets, between avenues, east-west) is about three short blocks.