Can take a shot... Does positive integer z equal 5? (1) z is not a factor of 42. Factors of 42: 1,2,3,6,7,14,21, 42. z is not equal to any of these numbers. This does not tell us anything else about z. It could be any other positive integer. Insufficient. (2) 5 is the largest divisor of z. Since 5 i...