Question 3: In the 7th century, ________ established the use of zero as a separate number and determined the results for multiplication, division, addition and subtraction of zero and all other numbers, except for the result of division by zero.

Question 6: Also, the ________ is the reciprocal of any number (except zero; zero is the only number without a multiplicative inverse), that is, multiplying the reciprocal of any number by the number itself will yield the multiplicative identity.

Question 7: The continuous historical development of modern arithmetic starts with the ________ of ancient Greece, although it originated much later than the Babylonian and Egyptian examples.

Question 10: The early number systems which included positional notation were not decimal, including the ________ system for Babylonian numerals and the vigesimal system which defined Maya numerals.