Changes

    

    

'''H5.'''  Without zero as a concept, algebra and every other kind of mathematics would be extremely difficult, especially with the Arabic numerals used by us today.  Numbers such as 10 and 100 would be difficult to express, and it would be hard to make the jump from negative numbers to positive numbers.  (3, 2, 1, -1,-2 does not work as well).

'''H5.'''  Without zero as a concept, algebra and every other kind of mathematics would be extremely difficult, especially with the Arabic numerals used by us today.  Numbers such as 10 and 100 would be difficult to express, and it would be hard to make the jump from negative numbers to positive numbers.  (3, 2, 1, -1,-2 does not work as well).