Which of the following sets are well-ordered? a. The set of all even integers. b. The set of all primes. c. f100; 99; 98; : : :; 98; 99; 100g. d. ;. e. The negative integers. f. f; 2 ; 3 ; 4 ; : : :g where is the familiar real number 3:14159 : : : .

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